xref: /aosp_15_r20/external/llvm/lib/CodeGen/AsmPrinter/WinException.cpp (revision 9880d6810fe72a1726cb53787c6711e909410d58)
1*9880d681SAndroid Build Coastguard Worker //===-- CodeGen/AsmPrinter/WinException.cpp - Dwarf Exception Impl ------===//
2*9880d681SAndroid Build Coastguard Worker //
3*9880d681SAndroid Build Coastguard Worker //                     The LLVM Compiler Infrastructure
4*9880d681SAndroid Build Coastguard Worker //
5*9880d681SAndroid Build Coastguard Worker // This file is distributed under the University of Illinois Open Source
6*9880d681SAndroid Build Coastguard Worker // License. See LICENSE.TXT for details.
7*9880d681SAndroid Build Coastguard Worker //
8*9880d681SAndroid Build Coastguard Worker //===----------------------------------------------------------------------===//
9*9880d681SAndroid Build Coastguard Worker //
10*9880d681SAndroid Build Coastguard Worker // This file contains support for writing Win64 exception info into asm files.
11*9880d681SAndroid Build Coastguard Worker //
12*9880d681SAndroid Build Coastguard Worker //===----------------------------------------------------------------------===//
13*9880d681SAndroid Build Coastguard Worker 
14*9880d681SAndroid Build Coastguard Worker #include "WinException.h"
15*9880d681SAndroid Build Coastguard Worker #include "llvm/ADT/StringExtras.h"
16*9880d681SAndroid Build Coastguard Worker #include "llvm/ADT/Twine.h"
17*9880d681SAndroid Build Coastguard Worker #include "llvm/CodeGen/AsmPrinter.h"
18*9880d681SAndroid Build Coastguard Worker #include "llvm/CodeGen/MachineFrameInfo.h"
19*9880d681SAndroid Build Coastguard Worker #include "llvm/CodeGen/MachineFunction.h"
20*9880d681SAndroid Build Coastguard Worker #include "llvm/CodeGen/MachineModuleInfo.h"
21*9880d681SAndroid Build Coastguard Worker #include "llvm/CodeGen/WinEHFuncInfo.h"
22*9880d681SAndroid Build Coastguard Worker #include "llvm/IR/DataLayout.h"
23*9880d681SAndroid Build Coastguard Worker #include "llvm/IR/Mangler.h"
24*9880d681SAndroid Build Coastguard Worker #include "llvm/IR/Module.h"
25*9880d681SAndroid Build Coastguard Worker #include "llvm/MC/MCAsmInfo.h"
26*9880d681SAndroid Build Coastguard Worker #include "llvm/MC/MCContext.h"
27*9880d681SAndroid Build Coastguard Worker #include "llvm/MC/MCExpr.h"
28*9880d681SAndroid Build Coastguard Worker #include "llvm/MC/MCSection.h"
29*9880d681SAndroid Build Coastguard Worker #include "llvm/MC/MCStreamer.h"
30*9880d681SAndroid Build Coastguard Worker #include "llvm/MC/MCSymbol.h"
31*9880d681SAndroid Build Coastguard Worker #include "llvm/MC/MCWin64EH.h"
32*9880d681SAndroid Build Coastguard Worker #include "llvm/Support/COFF.h"
33*9880d681SAndroid Build Coastguard Worker #include "llvm/Support/Dwarf.h"
34*9880d681SAndroid Build Coastguard Worker #include "llvm/Support/ErrorHandling.h"
35*9880d681SAndroid Build Coastguard Worker #include "llvm/Support/FormattedStream.h"
36*9880d681SAndroid Build Coastguard Worker #include "llvm/Target/TargetFrameLowering.h"
37*9880d681SAndroid Build Coastguard Worker #include "llvm/Target/TargetLowering.h"
38*9880d681SAndroid Build Coastguard Worker #include "llvm/Target/TargetLoweringObjectFile.h"
39*9880d681SAndroid Build Coastguard Worker #include "llvm/Target/TargetOptions.h"
40*9880d681SAndroid Build Coastguard Worker #include "llvm/Target/TargetRegisterInfo.h"
41*9880d681SAndroid Build Coastguard Worker #include "llvm/Target/TargetSubtargetInfo.h"
42*9880d681SAndroid Build Coastguard Worker using namespace llvm;
43*9880d681SAndroid Build Coastguard Worker 
WinException(AsmPrinter * A)44*9880d681SAndroid Build Coastguard Worker WinException::WinException(AsmPrinter *A) : EHStreamer(A) {
45*9880d681SAndroid Build Coastguard Worker   // MSVC's EH tables are always composed of 32-bit words.  All known 64-bit
46*9880d681SAndroid Build Coastguard Worker   // platforms use an imagerel32 relocation to refer to symbols.
47*9880d681SAndroid Build Coastguard Worker   useImageRel32 = (A->getDataLayout().getPointerSizeInBits() == 64);
48*9880d681SAndroid Build Coastguard Worker }
49*9880d681SAndroid Build Coastguard Worker 
~WinException()50*9880d681SAndroid Build Coastguard Worker WinException::~WinException() {}
51*9880d681SAndroid Build Coastguard Worker 
52*9880d681SAndroid Build Coastguard Worker /// endModule - Emit all exception information that should come after the
53*9880d681SAndroid Build Coastguard Worker /// content.
endModule()54*9880d681SAndroid Build Coastguard Worker void WinException::endModule() {
55*9880d681SAndroid Build Coastguard Worker   auto &OS = *Asm->OutStreamer;
56*9880d681SAndroid Build Coastguard Worker   const Module *M = MMI->getModule();
57*9880d681SAndroid Build Coastguard Worker   for (const Function &F : *M)
58*9880d681SAndroid Build Coastguard Worker     if (F.hasFnAttribute("safeseh"))
59*9880d681SAndroid Build Coastguard Worker       OS.EmitCOFFSafeSEH(Asm->getSymbol(&F));
60*9880d681SAndroid Build Coastguard Worker }
61*9880d681SAndroid Build Coastguard Worker 
beginFunction(const MachineFunction * MF)62*9880d681SAndroid Build Coastguard Worker void WinException::beginFunction(const MachineFunction *MF) {
63*9880d681SAndroid Build Coastguard Worker   shouldEmitMoves = shouldEmitPersonality = shouldEmitLSDA = false;
64*9880d681SAndroid Build Coastguard Worker 
65*9880d681SAndroid Build Coastguard Worker   // If any landing pads survive, we need an EH table.
66*9880d681SAndroid Build Coastguard Worker   bool hasLandingPads = !MMI->getLandingPads().empty();
67*9880d681SAndroid Build Coastguard Worker   bool hasEHFunclets = MMI->hasEHFunclets();
68*9880d681SAndroid Build Coastguard Worker 
69*9880d681SAndroid Build Coastguard Worker   const Function *F = MF->getFunction();
70*9880d681SAndroid Build Coastguard Worker 
71*9880d681SAndroid Build Coastguard Worker   shouldEmitMoves = Asm->needsSEHMoves();
72*9880d681SAndroid Build Coastguard Worker 
73*9880d681SAndroid Build Coastguard Worker   const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
74*9880d681SAndroid Build Coastguard Worker   unsigned PerEncoding = TLOF.getPersonalityEncoding();
75*9880d681SAndroid Build Coastguard Worker   const Function *Per = nullptr;
76*9880d681SAndroid Build Coastguard Worker   if (F->hasPersonalityFn())
77*9880d681SAndroid Build Coastguard Worker     Per = dyn_cast<Function>(F->getPersonalityFn()->stripPointerCasts());
78*9880d681SAndroid Build Coastguard Worker 
79*9880d681SAndroid Build Coastguard Worker   bool forceEmitPersonality =
80*9880d681SAndroid Build Coastguard Worker     F->hasPersonalityFn() && !isNoOpWithoutInvoke(classifyEHPersonality(Per)) &&
81*9880d681SAndroid Build Coastguard Worker     F->needsUnwindTableEntry();
82*9880d681SAndroid Build Coastguard Worker 
83*9880d681SAndroid Build Coastguard Worker   shouldEmitPersonality =
84*9880d681SAndroid Build Coastguard Worker       forceEmitPersonality || ((hasLandingPads || hasEHFunclets) &&
85*9880d681SAndroid Build Coastguard Worker                                PerEncoding != dwarf::DW_EH_PE_omit && Per);
86*9880d681SAndroid Build Coastguard Worker 
87*9880d681SAndroid Build Coastguard Worker   unsigned LSDAEncoding = TLOF.getLSDAEncoding();
88*9880d681SAndroid Build Coastguard Worker   shouldEmitLSDA = shouldEmitPersonality &&
89*9880d681SAndroid Build Coastguard Worker     LSDAEncoding != dwarf::DW_EH_PE_omit;
90*9880d681SAndroid Build Coastguard Worker 
91*9880d681SAndroid Build Coastguard Worker   // If we're not using CFI, we don't want the CFI or the personality, but we
92*9880d681SAndroid Build Coastguard Worker   // might want EH tables if we had EH pads.
93*9880d681SAndroid Build Coastguard Worker   if (!Asm->MAI->usesWindowsCFI()) {
94*9880d681SAndroid Build Coastguard Worker     shouldEmitLSDA = hasEHFunclets;
95*9880d681SAndroid Build Coastguard Worker     shouldEmitPersonality = false;
96*9880d681SAndroid Build Coastguard Worker     return;
97*9880d681SAndroid Build Coastguard Worker   }
98*9880d681SAndroid Build Coastguard Worker 
99*9880d681SAndroid Build Coastguard Worker   beginFunclet(MF->front(), Asm->CurrentFnSym);
100*9880d681SAndroid Build Coastguard Worker }
101*9880d681SAndroid Build Coastguard Worker 
102*9880d681SAndroid Build Coastguard Worker /// endFunction - Gather and emit post-function exception information.
103*9880d681SAndroid Build Coastguard Worker ///
endFunction(const MachineFunction * MF)104*9880d681SAndroid Build Coastguard Worker void WinException::endFunction(const MachineFunction *MF) {
105*9880d681SAndroid Build Coastguard Worker   if (!shouldEmitPersonality && !shouldEmitMoves && !shouldEmitLSDA)
106*9880d681SAndroid Build Coastguard Worker     return;
107*9880d681SAndroid Build Coastguard Worker 
108*9880d681SAndroid Build Coastguard Worker   const Function *F = MF->getFunction();
109*9880d681SAndroid Build Coastguard Worker   EHPersonality Per = EHPersonality::Unknown;
110*9880d681SAndroid Build Coastguard Worker   if (F->hasPersonalityFn())
111*9880d681SAndroid Build Coastguard Worker     Per = classifyEHPersonality(F->getPersonalityFn());
112*9880d681SAndroid Build Coastguard Worker 
113*9880d681SAndroid Build Coastguard Worker   // Get rid of any dead landing pads if we're not using funclets. In funclet
114*9880d681SAndroid Build Coastguard Worker   // schemes, the landing pad is not actually reachable. It only exists so
115*9880d681SAndroid Build Coastguard Worker   // that we can emit the right table data.
116*9880d681SAndroid Build Coastguard Worker   if (!isFuncletEHPersonality(Per))
117*9880d681SAndroid Build Coastguard Worker     MMI->TidyLandingPads();
118*9880d681SAndroid Build Coastguard Worker 
119*9880d681SAndroid Build Coastguard Worker   endFunclet();
120*9880d681SAndroid Build Coastguard Worker 
121*9880d681SAndroid Build Coastguard Worker   // endFunclet will emit the necessary .xdata tables for x64 SEH.
122*9880d681SAndroid Build Coastguard Worker   if (Per == EHPersonality::MSVC_Win64SEH && MMI->hasEHFunclets())
123*9880d681SAndroid Build Coastguard Worker     return;
124*9880d681SAndroid Build Coastguard Worker 
125*9880d681SAndroid Build Coastguard Worker   if (shouldEmitPersonality || shouldEmitLSDA) {
126*9880d681SAndroid Build Coastguard Worker     Asm->OutStreamer->PushSection();
127*9880d681SAndroid Build Coastguard Worker 
128*9880d681SAndroid Build Coastguard Worker     // Just switch sections to the right xdata section.
129*9880d681SAndroid Build Coastguard Worker     MCSection *XData = Asm->OutStreamer->getAssociatedXDataSection(
130*9880d681SAndroid Build Coastguard Worker         Asm->OutStreamer->getCurrentSectionOnly());
131*9880d681SAndroid Build Coastguard Worker     Asm->OutStreamer->SwitchSection(XData);
132*9880d681SAndroid Build Coastguard Worker 
133*9880d681SAndroid Build Coastguard Worker     // Emit the tables appropriate to the personality function in use. If we
134*9880d681SAndroid Build Coastguard Worker     // don't recognize the personality, assume it uses an Itanium-style LSDA.
135*9880d681SAndroid Build Coastguard Worker     if (Per == EHPersonality::MSVC_Win64SEH)
136*9880d681SAndroid Build Coastguard Worker       emitCSpecificHandlerTable(MF);
137*9880d681SAndroid Build Coastguard Worker     else if (Per == EHPersonality::MSVC_X86SEH)
138*9880d681SAndroid Build Coastguard Worker       emitExceptHandlerTable(MF);
139*9880d681SAndroid Build Coastguard Worker     else if (Per == EHPersonality::MSVC_CXX)
140*9880d681SAndroid Build Coastguard Worker       emitCXXFrameHandler3Table(MF);
141*9880d681SAndroid Build Coastguard Worker     else if (Per == EHPersonality::CoreCLR)
142*9880d681SAndroid Build Coastguard Worker       emitCLRExceptionTable(MF);
143*9880d681SAndroid Build Coastguard Worker     else
144*9880d681SAndroid Build Coastguard Worker       emitExceptionTable();
145*9880d681SAndroid Build Coastguard Worker 
146*9880d681SAndroid Build Coastguard Worker     Asm->OutStreamer->PopSection();
147*9880d681SAndroid Build Coastguard Worker   }
148*9880d681SAndroid Build Coastguard Worker }
149*9880d681SAndroid Build Coastguard Worker 
150*9880d681SAndroid Build Coastguard Worker /// Retreive the MCSymbol for a GlobalValue or MachineBasicBlock.
getMCSymbolForMBB(AsmPrinter * Asm,const MachineBasicBlock * MBB)151*9880d681SAndroid Build Coastguard Worker static MCSymbol *getMCSymbolForMBB(AsmPrinter *Asm,
152*9880d681SAndroid Build Coastguard Worker                                    const MachineBasicBlock *MBB) {
153*9880d681SAndroid Build Coastguard Worker   if (!MBB)
154*9880d681SAndroid Build Coastguard Worker     return nullptr;
155*9880d681SAndroid Build Coastguard Worker 
156*9880d681SAndroid Build Coastguard Worker   assert(MBB->isEHFuncletEntry());
157*9880d681SAndroid Build Coastguard Worker 
158*9880d681SAndroid Build Coastguard Worker   // Give catches and cleanups a name based off of their parent function and
159*9880d681SAndroid Build Coastguard Worker   // their funclet entry block's number.
160*9880d681SAndroid Build Coastguard Worker   const MachineFunction *MF = MBB->getParent();
161*9880d681SAndroid Build Coastguard Worker   const Function *F = MF->getFunction();
162*9880d681SAndroid Build Coastguard Worker   StringRef FuncLinkageName = GlobalValue::getRealLinkageName(F->getName());
163*9880d681SAndroid Build Coastguard Worker   MCContext &Ctx = MF->getContext();
164*9880d681SAndroid Build Coastguard Worker   StringRef HandlerPrefix = MBB->isCleanupFuncletEntry() ? "dtor" : "catch";
165*9880d681SAndroid Build Coastguard Worker   return Ctx.getOrCreateSymbol("?" + HandlerPrefix + "$" +
166*9880d681SAndroid Build Coastguard Worker                                Twine(MBB->getNumber()) + "@?0?" +
167*9880d681SAndroid Build Coastguard Worker                                FuncLinkageName + "@4HA");
168*9880d681SAndroid Build Coastguard Worker }
169*9880d681SAndroid Build Coastguard Worker 
beginFunclet(const MachineBasicBlock & MBB,MCSymbol * Sym)170*9880d681SAndroid Build Coastguard Worker void WinException::beginFunclet(const MachineBasicBlock &MBB,
171*9880d681SAndroid Build Coastguard Worker                                 MCSymbol *Sym) {
172*9880d681SAndroid Build Coastguard Worker   CurrentFuncletEntry = &MBB;
173*9880d681SAndroid Build Coastguard Worker 
174*9880d681SAndroid Build Coastguard Worker   const Function *F = Asm->MF->getFunction();
175*9880d681SAndroid Build Coastguard Worker   // If a symbol was not provided for the funclet, invent one.
176*9880d681SAndroid Build Coastguard Worker   if (!Sym) {
177*9880d681SAndroid Build Coastguard Worker     Sym = getMCSymbolForMBB(Asm, &MBB);
178*9880d681SAndroid Build Coastguard Worker 
179*9880d681SAndroid Build Coastguard Worker     // Describe our funclet symbol as a function with internal linkage.
180*9880d681SAndroid Build Coastguard Worker     Asm->OutStreamer->BeginCOFFSymbolDef(Sym);
181*9880d681SAndroid Build Coastguard Worker     Asm->OutStreamer->EmitCOFFSymbolStorageClass(COFF::IMAGE_SYM_CLASS_STATIC);
182*9880d681SAndroid Build Coastguard Worker     Asm->OutStreamer->EmitCOFFSymbolType(COFF::IMAGE_SYM_DTYPE_FUNCTION
183*9880d681SAndroid Build Coastguard Worker                                          << COFF::SCT_COMPLEX_TYPE_SHIFT);
184*9880d681SAndroid Build Coastguard Worker     Asm->OutStreamer->EndCOFFSymbolDef();
185*9880d681SAndroid Build Coastguard Worker 
186*9880d681SAndroid Build Coastguard Worker     // We want our funclet's entry point to be aligned such that no nops will be
187*9880d681SAndroid Build Coastguard Worker     // present after the label.
188*9880d681SAndroid Build Coastguard Worker     Asm->EmitAlignment(std::max(Asm->MF->getAlignment(), MBB.getAlignment()),
189*9880d681SAndroid Build Coastguard Worker                        F);
190*9880d681SAndroid Build Coastguard Worker 
191*9880d681SAndroid Build Coastguard Worker     // Now that we've emitted the alignment directive, point at our funclet.
192*9880d681SAndroid Build Coastguard Worker     Asm->OutStreamer->EmitLabel(Sym);
193*9880d681SAndroid Build Coastguard Worker   }
194*9880d681SAndroid Build Coastguard Worker 
195*9880d681SAndroid Build Coastguard Worker   // Mark 'Sym' as starting our funclet.
196*9880d681SAndroid Build Coastguard Worker   if (shouldEmitMoves || shouldEmitPersonality)
197*9880d681SAndroid Build Coastguard Worker     Asm->OutStreamer->EmitWinCFIStartProc(Sym);
198*9880d681SAndroid Build Coastguard Worker 
199*9880d681SAndroid Build Coastguard Worker   if (shouldEmitPersonality) {
200*9880d681SAndroid Build Coastguard Worker     const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
201*9880d681SAndroid Build Coastguard Worker     const Function *PerFn = nullptr;
202*9880d681SAndroid Build Coastguard Worker 
203*9880d681SAndroid Build Coastguard Worker     // Determine which personality routine we are using for this funclet.
204*9880d681SAndroid Build Coastguard Worker     if (F->hasPersonalityFn())
205*9880d681SAndroid Build Coastguard Worker       PerFn = dyn_cast<Function>(F->getPersonalityFn()->stripPointerCasts());
206*9880d681SAndroid Build Coastguard Worker     const MCSymbol *PersHandlerSym =
207*9880d681SAndroid Build Coastguard Worker         TLOF.getCFIPersonalitySymbol(PerFn, *Asm->Mang, Asm->TM, MMI);
208*9880d681SAndroid Build Coastguard Worker 
209*9880d681SAndroid Build Coastguard Worker     // Classify the personality routine so that we may reason about it.
210*9880d681SAndroid Build Coastguard Worker     EHPersonality Per = EHPersonality::Unknown;
211*9880d681SAndroid Build Coastguard Worker     if (F->hasPersonalityFn())
212*9880d681SAndroid Build Coastguard Worker       Per = classifyEHPersonality(F->getPersonalityFn());
213*9880d681SAndroid Build Coastguard Worker 
214*9880d681SAndroid Build Coastguard Worker     // Do not emit a .seh_handler directive if it is a C++ cleanup funclet.
215*9880d681SAndroid Build Coastguard Worker     if (Per != EHPersonality::MSVC_CXX ||
216*9880d681SAndroid Build Coastguard Worker         !CurrentFuncletEntry->isCleanupFuncletEntry())
217*9880d681SAndroid Build Coastguard Worker       Asm->OutStreamer->EmitWinEHHandler(PersHandlerSym, true, true);
218*9880d681SAndroid Build Coastguard Worker   }
219*9880d681SAndroid Build Coastguard Worker }
220*9880d681SAndroid Build Coastguard Worker 
endFunclet()221*9880d681SAndroid Build Coastguard Worker void WinException::endFunclet() {
222*9880d681SAndroid Build Coastguard Worker   // No funclet to process?  Great, we have nothing to do.
223*9880d681SAndroid Build Coastguard Worker   if (!CurrentFuncletEntry)
224*9880d681SAndroid Build Coastguard Worker     return;
225*9880d681SAndroid Build Coastguard Worker 
226*9880d681SAndroid Build Coastguard Worker   if (shouldEmitMoves || shouldEmitPersonality) {
227*9880d681SAndroid Build Coastguard Worker     const Function *F = Asm->MF->getFunction();
228*9880d681SAndroid Build Coastguard Worker     EHPersonality Per = EHPersonality::Unknown;
229*9880d681SAndroid Build Coastguard Worker     if (F->hasPersonalityFn())
230*9880d681SAndroid Build Coastguard Worker       Per = classifyEHPersonality(F->getPersonalityFn());
231*9880d681SAndroid Build Coastguard Worker 
232*9880d681SAndroid Build Coastguard Worker     // The .seh_handlerdata directive implicitly switches section, push the
233*9880d681SAndroid Build Coastguard Worker     // current section so that we may return to it.
234*9880d681SAndroid Build Coastguard Worker     Asm->OutStreamer->PushSection();
235*9880d681SAndroid Build Coastguard Worker 
236*9880d681SAndroid Build Coastguard Worker     // Emit an UNWIND_INFO struct describing the prologue.
237*9880d681SAndroid Build Coastguard Worker     Asm->OutStreamer->EmitWinEHHandlerData();
238*9880d681SAndroid Build Coastguard Worker 
239*9880d681SAndroid Build Coastguard Worker     if (Per == EHPersonality::MSVC_CXX && shouldEmitPersonality &&
240*9880d681SAndroid Build Coastguard Worker         !CurrentFuncletEntry->isCleanupFuncletEntry()) {
241*9880d681SAndroid Build Coastguard Worker       // If this is a C++ catch funclet (or the parent function),
242*9880d681SAndroid Build Coastguard Worker       // emit a reference to the LSDA for the parent function.
243*9880d681SAndroid Build Coastguard Worker       StringRef FuncLinkageName = GlobalValue::getRealLinkageName(F->getName());
244*9880d681SAndroid Build Coastguard Worker       MCSymbol *FuncInfoXData = Asm->OutContext.getOrCreateSymbol(
245*9880d681SAndroid Build Coastguard Worker           Twine("$cppxdata$", FuncLinkageName));
246*9880d681SAndroid Build Coastguard Worker       Asm->OutStreamer->EmitValue(create32bitRef(FuncInfoXData), 4);
247*9880d681SAndroid Build Coastguard Worker     } else if (Per == EHPersonality::MSVC_Win64SEH && MMI->hasEHFunclets() &&
248*9880d681SAndroid Build Coastguard Worker                !CurrentFuncletEntry->isEHFuncletEntry()) {
249*9880d681SAndroid Build Coastguard Worker       // If this is the parent function in Win64 SEH, emit the LSDA immediately
250*9880d681SAndroid Build Coastguard Worker       // following .seh_handlerdata.
251*9880d681SAndroid Build Coastguard Worker       emitCSpecificHandlerTable(Asm->MF);
252*9880d681SAndroid Build Coastguard Worker     }
253*9880d681SAndroid Build Coastguard Worker 
254*9880d681SAndroid Build Coastguard Worker     // Switch back to the previous section now that we are done writing to
255*9880d681SAndroid Build Coastguard Worker     // .xdata.
256*9880d681SAndroid Build Coastguard Worker     Asm->OutStreamer->PopSection();
257*9880d681SAndroid Build Coastguard Worker 
258*9880d681SAndroid Build Coastguard Worker     // Emit a .seh_endproc directive to mark the end of the function.
259*9880d681SAndroid Build Coastguard Worker     Asm->OutStreamer->EmitWinCFIEndProc();
260*9880d681SAndroid Build Coastguard Worker   }
261*9880d681SAndroid Build Coastguard Worker 
262*9880d681SAndroid Build Coastguard Worker   // Let's make sure we don't try to end the same funclet twice.
263*9880d681SAndroid Build Coastguard Worker   CurrentFuncletEntry = nullptr;
264*9880d681SAndroid Build Coastguard Worker }
265*9880d681SAndroid Build Coastguard Worker 
create32bitRef(const MCSymbol * Value)266*9880d681SAndroid Build Coastguard Worker const MCExpr *WinException::create32bitRef(const MCSymbol *Value) {
267*9880d681SAndroid Build Coastguard Worker   if (!Value)
268*9880d681SAndroid Build Coastguard Worker     return MCConstantExpr::create(0, Asm->OutContext);
269*9880d681SAndroid Build Coastguard Worker   return MCSymbolRefExpr::create(Value, useImageRel32
270*9880d681SAndroid Build Coastguard Worker                                             ? MCSymbolRefExpr::VK_COFF_IMGREL32
271*9880d681SAndroid Build Coastguard Worker                                             : MCSymbolRefExpr::VK_None,
272*9880d681SAndroid Build Coastguard Worker                                  Asm->OutContext);
273*9880d681SAndroid Build Coastguard Worker }
274*9880d681SAndroid Build Coastguard Worker 
create32bitRef(const GlobalValue * GV)275*9880d681SAndroid Build Coastguard Worker const MCExpr *WinException::create32bitRef(const GlobalValue *GV) {
276*9880d681SAndroid Build Coastguard Worker   if (!GV)
277*9880d681SAndroid Build Coastguard Worker     return MCConstantExpr::create(0, Asm->OutContext);
278*9880d681SAndroid Build Coastguard Worker   return create32bitRef(Asm->getSymbol(GV));
279*9880d681SAndroid Build Coastguard Worker }
280*9880d681SAndroid Build Coastguard Worker 
getLabelPlusOne(const MCSymbol * Label)281*9880d681SAndroid Build Coastguard Worker const MCExpr *WinException::getLabelPlusOne(const MCSymbol *Label) {
282*9880d681SAndroid Build Coastguard Worker   return MCBinaryExpr::createAdd(create32bitRef(Label),
283*9880d681SAndroid Build Coastguard Worker                                  MCConstantExpr::create(1, Asm->OutContext),
284*9880d681SAndroid Build Coastguard Worker                                  Asm->OutContext);
285*9880d681SAndroid Build Coastguard Worker }
286*9880d681SAndroid Build Coastguard Worker 
getOffset(const MCSymbol * OffsetOf,const MCSymbol * OffsetFrom)287*9880d681SAndroid Build Coastguard Worker const MCExpr *WinException::getOffset(const MCSymbol *OffsetOf,
288*9880d681SAndroid Build Coastguard Worker                                       const MCSymbol *OffsetFrom) {
289*9880d681SAndroid Build Coastguard Worker   return MCBinaryExpr::createSub(
290*9880d681SAndroid Build Coastguard Worker       MCSymbolRefExpr::create(OffsetOf, Asm->OutContext),
291*9880d681SAndroid Build Coastguard Worker       MCSymbolRefExpr::create(OffsetFrom, Asm->OutContext), Asm->OutContext);
292*9880d681SAndroid Build Coastguard Worker }
293*9880d681SAndroid Build Coastguard Worker 
getOffsetPlusOne(const MCSymbol * OffsetOf,const MCSymbol * OffsetFrom)294*9880d681SAndroid Build Coastguard Worker const MCExpr *WinException::getOffsetPlusOne(const MCSymbol *OffsetOf,
295*9880d681SAndroid Build Coastguard Worker                                              const MCSymbol *OffsetFrom) {
296*9880d681SAndroid Build Coastguard Worker   return MCBinaryExpr::createAdd(getOffset(OffsetOf, OffsetFrom),
297*9880d681SAndroid Build Coastguard Worker                                  MCConstantExpr::create(1, Asm->OutContext),
298*9880d681SAndroid Build Coastguard Worker                                  Asm->OutContext);
299*9880d681SAndroid Build Coastguard Worker }
300*9880d681SAndroid Build Coastguard Worker 
getFrameIndexOffset(int FrameIndex,const WinEHFuncInfo & FuncInfo)301*9880d681SAndroid Build Coastguard Worker int WinException::getFrameIndexOffset(int FrameIndex,
302*9880d681SAndroid Build Coastguard Worker                                       const WinEHFuncInfo &FuncInfo) {
303*9880d681SAndroid Build Coastguard Worker   const TargetFrameLowering &TFI = *Asm->MF->getSubtarget().getFrameLowering();
304*9880d681SAndroid Build Coastguard Worker   unsigned UnusedReg;
305*9880d681SAndroid Build Coastguard Worker   if (Asm->MAI->usesWindowsCFI()) {
306*9880d681SAndroid Build Coastguard Worker     int Offset =
307*9880d681SAndroid Build Coastguard Worker         TFI.getFrameIndexReferencePreferSP(*Asm->MF, FrameIndex, UnusedReg,
308*9880d681SAndroid Build Coastguard Worker                                            /*IgnoreSPUpdates*/ true);
309*9880d681SAndroid Build Coastguard Worker     assert(UnusedReg ==
310*9880d681SAndroid Build Coastguard Worker            Asm->MF->getSubtarget()
311*9880d681SAndroid Build Coastguard Worker                .getTargetLowering()
312*9880d681SAndroid Build Coastguard Worker                ->getStackPointerRegisterToSaveRestore());
313*9880d681SAndroid Build Coastguard Worker     return Offset;
314*9880d681SAndroid Build Coastguard Worker   }
315*9880d681SAndroid Build Coastguard Worker 
316*9880d681SAndroid Build Coastguard Worker   // For 32-bit, offsets should be relative to the end of the EH registration
317*9880d681SAndroid Build Coastguard Worker   // node. For 64-bit, it's relative to SP at the end of the prologue.
318*9880d681SAndroid Build Coastguard Worker   assert(FuncInfo.EHRegNodeEndOffset != INT_MAX);
319*9880d681SAndroid Build Coastguard Worker   int Offset = TFI.getFrameIndexReference(*Asm->MF, FrameIndex, UnusedReg);
320*9880d681SAndroid Build Coastguard Worker   Offset += FuncInfo.EHRegNodeEndOffset;
321*9880d681SAndroid Build Coastguard Worker   return Offset;
322*9880d681SAndroid Build Coastguard Worker }
323*9880d681SAndroid Build Coastguard Worker 
324*9880d681SAndroid Build Coastguard Worker namespace {
325*9880d681SAndroid Build Coastguard Worker 
326*9880d681SAndroid Build Coastguard Worker /// Top-level state used to represent unwind to caller
327*9880d681SAndroid Build Coastguard Worker const int NullState = -1;
328*9880d681SAndroid Build Coastguard Worker 
329*9880d681SAndroid Build Coastguard Worker struct InvokeStateChange {
330*9880d681SAndroid Build Coastguard Worker   /// EH Label immediately after the last invoke in the previous state, or
331*9880d681SAndroid Build Coastguard Worker   /// nullptr if the previous state was the null state.
332*9880d681SAndroid Build Coastguard Worker   const MCSymbol *PreviousEndLabel;
333*9880d681SAndroid Build Coastguard Worker 
334*9880d681SAndroid Build Coastguard Worker   /// EH label immediately before the first invoke in the new state, or nullptr
335*9880d681SAndroid Build Coastguard Worker   /// if the new state is the null state.
336*9880d681SAndroid Build Coastguard Worker   const MCSymbol *NewStartLabel;
337*9880d681SAndroid Build Coastguard Worker 
338*9880d681SAndroid Build Coastguard Worker   /// State of the invoke following NewStartLabel, or NullState to indicate
339*9880d681SAndroid Build Coastguard Worker   /// the presence of calls which may unwind to caller.
340*9880d681SAndroid Build Coastguard Worker   int NewState;
341*9880d681SAndroid Build Coastguard Worker };
342*9880d681SAndroid Build Coastguard Worker 
343*9880d681SAndroid Build Coastguard Worker /// Iterator that reports all the invoke state changes in a range of machine
344*9880d681SAndroid Build Coastguard Worker /// basic blocks.  Changes to the null state are reported whenever a call that
345*9880d681SAndroid Build Coastguard Worker /// may unwind to caller is encountered.  The MBB range is expected to be an
346*9880d681SAndroid Build Coastguard Worker /// entire function or funclet, and the start and end of the range are treated
347*9880d681SAndroid Build Coastguard Worker /// as being in the NullState even if there's not an unwind-to-caller call
348*9880d681SAndroid Build Coastguard Worker /// before the first invoke or after the last one (i.e., the first state change
349*9880d681SAndroid Build Coastguard Worker /// reported is the first change to something other than NullState, and a
350*9880d681SAndroid Build Coastguard Worker /// change back to NullState is always reported at the end of iteration).
351*9880d681SAndroid Build Coastguard Worker class InvokeStateChangeIterator {
InvokeStateChangeIterator(const WinEHFuncInfo & EHInfo,MachineFunction::const_iterator MFI,MachineFunction::const_iterator MFE,MachineBasicBlock::const_iterator MBBI,int BaseState)352*9880d681SAndroid Build Coastguard Worker   InvokeStateChangeIterator(const WinEHFuncInfo &EHInfo,
353*9880d681SAndroid Build Coastguard Worker                             MachineFunction::const_iterator MFI,
354*9880d681SAndroid Build Coastguard Worker                             MachineFunction::const_iterator MFE,
355*9880d681SAndroid Build Coastguard Worker                             MachineBasicBlock::const_iterator MBBI,
356*9880d681SAndroid Build Coastguard Worker                             int BaseState)
357*9880d681SAndroid Build Coastguard Worker       : EHInfo(EHInfo), MFI(MFI), MFE(MFE), MBBI(MBBI), BaseState(BaseState) {
358*9880d681SAndroid Build Coastguard Worker     LastStateChange.PreviousEndLabel = nullptr;
359*9880d681SAndroid Build Coastguard Worker     LastStateChange.NewStartLabel = nullptr;
360*9880d681SAndroid Build Coastguard Worker     LastStateChange.NewState = BaseState;
361*9880d681SAndroid Build Coastguard Worker     scan();
362*9880d681SAndroid Build Coastguard Worker   }
363*9880d681SAndroid Build Coastguard Worker 
364*9880d681SAndroid Build Coastguard Worker public:
365*9880d681SAndroid Build Coastguard Worker   static iterator_range<InvokeStateChangeIterator>
range(const WinEHFuncInfo & EHInfo,MachineFunction::const_iterator Begin,MachineFunction::const_iterator End,int BaseState=NullState)366*9880d681SAndroid Build Coastguard Worker   range(const WinEHFuncInfo &EHInfo, MachineFunction::const_iterator Begin,
367*9880d681SAndroid Build Coastguard Worker         MachineFunction::const_iterator End, int BaseState = NullState) {
368*9880d681SAndroid Build Coastguard Worker     // Reject empty ranges to simplify bookkeeping by ensuring that we can get
369*9880d681SAndroid Build Coastguard Worker     // the end of the last block.
370*9880d681SAndroid Build Coastguard Worker     assert(Begin != End);
371*9880d681SAndroid Build Coastguard Worker     auto BlockBegin = Begin->begin();
372*9880d681SAndroid Build Coastguard Worker     auto BlockEnd = std::prev(End)->end();
373*9880d681SAndroid Build Coastguard Worker     return make_range(
374*9880d681SAndroid Build Coastguard Worker         InvokeStateChangeIterator(EHInfo, Begin, End, BlockBegin, BaseState),
375*9880d681SAndroid Build Coastguard Worker         InvokeStateChangeIterator(EHInfo, End, End, BlockEnd, BaseState));
376*9880d681SAndroid Build Coastguard Worker   }
377*9880d681SAndroid Build Coastguard Worker 
378*9880d681SAndroid Build Coastguard Worker   // Iterator methods.
operator ==(const InvokeStateChangeIterator & O) const379*9880d681SAndroid Build Coastguard Worker   bool operator==(const InvokeStateChangeIterator &O) const {
380*9880d681SAndroid Build Coastguard Worker     assert(BaseState == O.BaseState);
381*9880d681SAndroid Build Coastguard Worker     // Must be visiting same block.
382*9880d681SAndroid Build Coastguard Worker     if (MFI != O.MFI)
383*9880d681SAndroid Build Coastguard Worker       return false;
384*9880d681SAndroid Build Coastguard Worker     // Must be visiting same isntr.
385*9880d681SAndroid Build Coastguard Worker     if (MBBI != O.MBBI)
386*9880d681SAndroid Build Coastguard Worker       return false;
387*9880d681SAndroid Build Coastguard Worker     // At end of block/instr iteration, we can still have two distinct states:
388*9880d681SAndroid Build Coastguard Worker     // one to report the final EndLabel, and another indicating the end of the
389*9880d681SAndroid Build Coastguard Worker     // state change iteration.  Check for CurrentEndLabel equality to
390*9880d681SAndroid Build Coastguard Worker     // distinguish these.
391*9880d681SAndroid Build Coastguard Worker     return CurrentEndLabel == O.CurrentEndLabel;
392*9880d681SAndroid Build Coastguard Worker   }
393*9880d681SAndroid Build Coastguard Worker 
operator !=(const InvokeStateChangeIterator & O) const394*9880d681SAndroid Build Coastguard Worker   bool operator!=(const InvokeStateChangeIterator &O) const {
395*9880d681SAndroid Build Coastguard Worker     return !operator==(O);
396*9880d681SAndroid Build Coastguard Worker   }
operator *()397*9880d681SAndroid Build Coastguard Worker   InvokeStateChange &operator*() { return LastStateChange; }
operator ->()398*9880d681SAndroid Build Coastguard Worker   InvokeStateChange *operator->() { return &LastStateChange; }
operator ++()399*9880d681SAndroid Build Coastguard Worker   InvokeStateChangeIterator &operator++() { return scan(); }
400*9880d681SAndroid Build Coastguard Worker 
401*9880d681SAndroid Build Coastguard Worker private:
402*9880d681SAndroid Build Coastguard Worker   InvokeStateChangeIterator &scan();
403*9880d681SAndroid Build Coastguard Worker 
404*9880d681SAndroid Build Coastguard Worker   const WinEHFuncInfo &EHInfo;
405*9880d681SAndroid Build Coastguard Worker   const MCSymbol *CurrentEndLabel = nullptr;
406*9880d681SAndroid Build Coastguard Worker   MachineFunction::const_iterator MFI;
407*9880d681SAndroid Build Coastguard Worker   MachineFunction::const_iterator MFE;
408*9880d681SAndroid Build Coastguard Worker   MachineBasicBlock::const_iterator MBBI;
409*9880d681SAndroid Build Coastguard Worker   InvokeStateChange LastStateChange;
410*9880d681SAndroid Build Coastguard Worker   bool VisitingInvoke = false;
411*9880d681SAndroid Build Coastguard Worker   int BaseState;
412*9880d681SAndroid Build Coastguard Worker };
413*9880d681SAndroid Build Coastguard Worker 
414*9880d681SAndroid Build Coastguard Worker } // end anonymous namespace
415*9880d681SAndroid Build Coastguard Worker 
scan()416*9880d681SAndroid Build Coastguard Worker InvokeStateChangeIterator &InvokeStateChangeIterator::scan() {
417*9880d681SAndroid Build Coastguard Worker   bool IsNewBlock = false;
418*9880d681SAndroid Build Coastguard Worker   for (; MFI != MFE; ++MFI, IsNewBlock = true) {
419*9880d681SAndroid Build Coastguard Worker     if (IsNewBlock)
420*9880d681SAndroid Build Coastguard Worker       MBBI = MFI->begin();
421*9880d681SAndroid Build Coastguard Worker     for (auto MBBE = MFI->end(); MBBI != MBBE; ++MBBI) {
422*9880d681SAndroid Build Coastguard Worker       const MachineInstr &MI = *MBBI;
423*9880d681SAndroid Build Coastguard Worker       if (!VisitingInvoke && LastStateChange.NewState != BaseState &&
424*9880d681SAndroid Build Coastguard Worker           MI.isCall() && !EHStreamer::callToNoUnwindFunction(&MI)) {
425*9880d681SAndroid Build Coastguard Worker         // Indicate a change of state to the null state.  We don't have
426*9880d681SAndroid Build Coastguard Worker         // start/end EH labels handy but the caller won't expect them for
427*9880d681SAndroid Build Coastguard Worker         // null state regions.
428*9880d681SAndroid Build Coastguard Worker         LastStateChange.PreviousEndLabel = CurrentEndLabel;
429*9880d681SAndroid Build Coastguard Worker         LastStateChange.NewStartLabel = nullptr;
430*9880d681SAndroid Build Coastguard Worker         LastStateChange.NewState = BaseState;
431*9880d681SAndroid Build Coastguard Worker         CurrentEndLabel = nullptr;
432*9880d681SAndroid Build Coastguard Worker         // Don't re-visit this instr on the next scan
433*9880d681SAndroid Build Coastguard Worker         ++MBBI;
434*9880d681SAndroid Build Coastguard Worker         return *this;
435*9880d681SAndroid Build Coastguard Worker       }
436*9880d681SAndroid Build Coastguard Worker 
437*9880d681SAndroid Build Coastguard Worker       // All other state changes are at EH labels before/after invokes.
438*9880d681SAndroid Build Coastguard Worker       if (!MI.isEHLabel())
439*9880d681SAndroid Build Coastguard Worker         continue;
440*9880d681SAndroid Build Coastguard Worker       MCSymbol *Label = MI.getOperand(0).getMCSymbol();
441*9880d681SAndroid Build Coastguard Worker       if (Label == CurrentEndLabel) {
442*9880d681SAndroid Build Coastguard Worker         VisitingInvoke = false;
443*9880d681SAndroid Build Coastguard Worker         continue;
444*9880d681SAndroid Build Coastguard Worker       }
445*9880d681SAndroid Build Coastguard Worker       auto InvokeMapIter = EHInfo.LabelToStateMap.find(Label);
446*9880d681SAndroid Build Coastguard Worker       // Ignore EH labels that aren't the ones inserted before an invoke
447*9880d681SAndroid Build Coastguard Worker       if (InvokeMapIter == EHInfo.LabelToStateMap.end())
448*9880d681SAndroid Build Coastguard Worker         continue;
449*9880d681SAndroid Build Coastguard Worker       auto &StateAndEnd = InvokeMapIter->second;
450*9880d681SAndroid Build Coastguard Worker       int NewState = StateAndEnd.first;
451*9880d681SAndroid Build Coastguard Worker       // Keep track of the fact that we're between EH start/end labels so
452*9880d681SAndroid Build Coastguard Worker       // we know not to treat the inoke we'll see as unwinding to caller.
453*9880d681SAndroid Build Coastguard Worker       VisitingInvoke = true;
454*9880d681SAndroid Build Coastguard Worker       if (NewState == LastStateChange.NewState) {
455*9880d681SAndroid Build Coastguard Worker         // The state isn't actually changing here.  Record the new end and
456*9880d681SAndroid Build Coastguard Worker         // keep going.
457*9880d681SAndroid Build Coastguard Worker         CurrentEndLabel = StateAndEnd.second;
458*9880d681SAndroid Build Coastguard Worker         continue;
459*9880d681SAndroid Build Coastguard Worker       }
460*9880d681SAndroid Build Coastguard Worker       // Found a state change to report
461*9880d681SAndroid Build Coastguard Worker       LastStateChange.PreviousEndLabel = CurrentEndLabel;
462*9880d681SAndroid Build Coastguard Worker       LastStateChange.NewStartLabel = Label;
463*9880d681SAndroid Build Coastguard Worker       LastStateChange.NewState = NewState;
464*9880d681SAndroid Build Coastguard Worker       // Start keeping track of the new current end
465*9880d681SAndroid Build Coastguard Worker       CurrentEndLabel = StateAndEnd.second;
466*9880d681SAndroid Build Coastguard Worker       // Don't re-visit this instr on the next scan
467*9880d681SAndroid Build Coastguard Worker       ++MBBI;
468*9880d681SAndroid Build Coastguard Worker       return *this;
469*9880d681SAndroid Build Coastguard Worker     }
470*9880d681SAndroid Build Coastguard Worker   }
471*9880d681SAndroid Build Coastguard Worker   // Iteration hit the end of the block range.
472*9880d681SAndroid Build Coastguard Worker   if (LastStateChange.NewState != BaseState) {
473*9880d681SAndroid Build Coastguard Worker     // Report the end of the last new state
474*9880d681SAndroid Build Coastguard Worker     LastStateChange.PreviousEndLabel = CurrentEndLabel;
475*9880d681SAndroid Build Coastguard Worker     LastStateChange.NewStartLabel = nullptr;
476*9880d681SAndroid Build Coastguard Worker     LastStateChange.NewState = BaseState;
477*9880d681SAndroid Build Coastguard Worker     // Leave CurrentEndLabel non-null to distinguish this state from end.
478*9880d681SAndroid Build Coastguard Worker     assert(CurrentEndLabel != nullptr);
479*9880d681SAndroid Build Coastguard Worker     return *this;
480*9880d681SAndroid Build Coastguard Worker   }
481*9880d681SAndroid Build Coastguard Worker   // We've reported all state changes and hit the end state.
482*9880d681SAndroid Build Coastguard Worker   CurrentEndLabel = nullptr;
483*9880d681SAndroid Build Coastguard Worker   return *this;
484*9880d681SAndroid Build Coastguard Worker }
485*9880d681SAndroid Build Coastguard Worker 
486*9880d681SAndroid Build Coastguard Worker /// Emit the language-specific data that __C_specific_handler expects.  This
487*9880d681SAndroid Build Coastguard Worker /// handler lives in the x64 Microsoft C runtime and allows catching or cleaning
488*9880d681SAndroid Build Coastguard Worker /// up after faults with __try, __except, and __finally.  The typeinfo values
489*9880d681SAndroid Build Coastguard Worker /// are not really RTTI data, but pointers to filter functions that return an
490*9880d681SAndroid Build Coastguard Worker /// integer (1, 0, or -1) indicating how to handle the exception. For __finally
491*9880d681SAndroid Build Coastguard Worker /// blocks and other cleanups, the landing pad label is zero, and the filter
492*9880d681SAndroid Build Coastguard Worker /// function is actually a cleanup handler with the same prototype.  A catch-all
493*9880d681SAndroid Build Coastguard Worker /// entry is modeled with a null filter function field and a non-zero landing
494*9880d681SAndroid Build Coastguard Worker /// pad label.
495*9880d681SAndroid Build Coastguard Worker ///
496*9880d681SAndroid Build Coastguard Worker /// Possible filter function return values:
497*9880d681SAndroid Build Coastguard Worker ///   EXCEPTION_EXECUTE_HANDLER (1):
498*9880d681SAndroid Build Coastguard Worker ///     Jump to the landing pad label after cleanups.
499*9880d681SAndroid Build Coastguard Worker ///   EXCEPTION_CONTINUE_SEARCH (0):
500*9880d681SAndroid Build Coastguard Worker ///     Continue searching this table or continue unwinding.
501*9880d681SAndroid Build Coastguard Worker ///   EXCEPTION_CONTINUE_EXECUTION (-1):
502*9880d681SAndroid Build Coastguard Worker ///     Resume execution at the trapping PC.
503*9880d681SAndroid Build Coastguard Worker ///
504*9880d681SAndroid Build Coastguard Worker /// Inferred table structure:
505*9880d681SAndroid Build Coastguard Worker ///   struct Table {
506*9880d681SAndroid Build Coastguard Worker ///     int NumEntries;
507*9880d681SAndroid Build Coastguard Worker ///     struct Entry {
508*9880d681SAndroid Build Coastguard Worker ///       imagerel32 LabelStart;
509*9880d681SAndroid Build Coastguard Worker ///       imagerel32 LabelEnd;
510*9880d681SAndroid Build Coastguard Worker ///       imagerel32 FilterOrFinally;  // One means catch-all.
511*9880d681SAndroid Build Coastguard Worker ///       imagerel32 LabelLPad;        // Zero means __finally.
512*9880d681SAndroid Build Coastguard Worker ///     } Entries[NumEntries];
513*9880d681SAndroid Build Coastguard Worker ///   };
emitCSpecificHandlerTable(const MachineFunction * MF)514*9880d681SAndroid Build Coastguard Worker void WinException::emitCSpecificHandlerTable(const MachineFunction *MF) {
515*9880d681SAndroid Build Coastguard Worker   auto &OS = *Asm->OutStreamer;
516*9880d681SAndroid Build Coastguard Worker   MCContext &Ctx = Asm->OutContext;
517*9880d681SAndroid Build Coastguard Worker   const WinEHFuncInfo &FuncInfo = *MF->getWinEHFuncInfo();
518*9880d681SAndroid Build Coastguard Worker 
519*9880d681SAndroid Build Coastguard Worker   bool VerboseAsm = OS.isVerboseAsm();
520*9880d681SAndroid Build Coastguard Worker   auto AddComment = [&](const Twine &Comment) {
521*9880d681SAndroid Build Coastguard Worker     if (VerboseAsm)
522*9880d681SAndroid Build Coastguard Worker       OS.AddComment(Comment);
523*9880d681SAndroid Build Coastguard Worker   };
524*9880d681SAndroid Build Coastguard Worker 
525*9880d681SAndroid Build Coastguard Worker   // Emit a label assignment with the SEH frame offset so we can use it for
526*9880d681SAndroid Build Coastguard Worker   // llvm.x86.seh.recoverfp.
527*9880d681SAndroid Build Coastguard Worker   StringRef FLinkageName =
528*9880d681SAndroid Build Coastguard Worker       GlobalValue::getRealLinkageName(MF->getFunction()->getName());
529*9880d681SAndroid Build Coastguard Worker   MCSymbol *ParentFrameOffset =
530*9880d681SAndroid Build Coastguard Worker       Ctx.getOrCreateParentFrameOffsetSymbol(FLinkageName);
531*9880d681SAndroid Build Coastguard Worker   const MCExpr *MCOffset =
532*9880d681SAndroid Build Coastguard Worker       MCConstantExpr::create(FuncInfo.SEHSetFrameOffset, Ctx);
533*9880d681SAndroid Build Coastguard Worker   Asm->OutStreamer->EmitAssignment(ParentFrameOffset, MCOffset);
534*9880d681SAndroid Build Coastguard Worker 
535*9880d681SAndroid Build Coastguard Worker   // Use the assembler to compute the number of table entries through label
536*9880d681SAndroid Build Coastguard Worker   // difference and division.
537*9880d681SAndroid Build Coastguard Worker   MCSymbol *TableBegin =
538*9880d681SAndroid Build Coastguard Worker       Ctx.createTempSymbol("lsda_begin", /*AlwaysAddSuffix=*/true);
539*9880d681SAndroid Build Coastguard Worker   MCSymbol *TableEnd =
540*9880d681SAndroid Build Coastguard Worker       Ctx.createTempSymbol("lsda_end", /*AlwaysAddSuffix=*/true);
541*9880d681SAndroid Build Coastguard Worker   const MCExpr *LabelDiff = getOffset(TableEnd, TableBegin);
542*9880d681SAndroid Build Coastguard Worker   const MCExpr *EntrySize = MCConstantExpr::create(16, Ctx);
543*9880d681SAndroid Build Coastguard Worker   const MCExpr *EntryCount = MCBinaryExpr::createDiv(LabelDiff, EntrySize, Ctx);
544*9880d681SAndroid Build Coastguard Worker   AddComment("Number of call sites");
545*9880d681SAndroid Build Coastguard Worker   OS.EmitValue(EntryCount, 4);
546*9880d681SAndroid Build Coastguard Worker 
547*9880d681SAndroid Build Coastguard Worker   OS.EmitLabel(TableBegin);
548*9880d681SAndroid Build Coastguard Worker 
549*9880d681SAndroid Build Coastguard Worker   // Iterate over all the invoke try ranges. Unlike MSVC, LLVM currently only
550*9880d681SAndroid Build Coastguard Worker   // models exceptions from invokes. LLVM also allows arbitrary reordering of
551*9880d681SAndroid Build Coastguard Worker   // the code, so our tables end up looking a bit different. Rather than
552*9880d681SAndroid Build Coastguard Worker   // trying to match MSVC's tables exactly, we emit a denormalized table.  For
553*9880d681SAndroid Build Coastguard Worker   // each range of invokes in the same state, we emit table entries for all
554*9880d681SAndroid Build Coastguard Worker   // the actions that would be taken in that state. This means our tables are
555*9880d681SAndroid Build Coastguard Worker   // slightly bigger, which is OK.
556*9880d681SAndroid Build Coastguard Worker   const MCSymbol *LastStartLabel = nullptr;
557*9880d681SAndroid Build Coastguard Worker   int LastEHState = -1;
558*9880d681SAndroid Build Coastguard Worker   // Break out before we enter into a finally funclet.
559*9880d681SAndroid Build Coastguard Worker   // FIXME: We need to emit separate EH tables for cleanups.
560*9880d681SAndroid Build Coastguard Worker   MachineFunction::const_iterator End = MF->end();
561*9880d681SAndroid Build Coastguard Worker   MachineFunction::const_iterator Stop = std::next(MF->begin());
562*9880d681SAndroid Build Coastguard Worker   while (Stop != End && !Stop->isEHFuncletEntry())
563*9880d681SAndroid Build Coastguard Worker     ++Stop;
564*9880d681SAndroid Build Coastguard Worker   for (const auto &StateChange :
565*9880d681SAndroid Build Coastguard Worker        InvokeStateChangeIterator::range(FuncInfo, MF->begin(), Stop)) {
566*9880d681SAndroid Build Coastguard Worker     // Emit all the actions for the state we just transitioned out of
567*9880d681SAndroid Build Coastguard Worker     // if it was not the null state
568*9880d681SAndroid Build Coastguard Worker     if (LastEHState != -1)
569*9880d681SAndroid Build Coastguard Worker       emitSEHActionsForRange(FuncInfo, LastStartLabel,
570*9880d681SAndroid Build Coastguard Worker                              StateChange.PreviousEndLabel, LastEHState);
571*9880d681SAndroid Build Coastguard Worker     LastStartLabel = StateChange.NewStartLabel;
572*9880d681SAndroid Build Coastguard Worker     LastEHState = StateChange.NewState;
573*9880d681SAndroid Build Coastguard Worker   }
574*9880d681SAndroid Build Coastguard Worker 
575*9880d681SAndroid Build Coastguard Worker   OS.EmitLabel(TableEnd);
576*9880d681SAndroid Build Coastguard Worker }
577*9880d681SAndroid Build Coastguard Worker 
emitSEHActionsForRange(const WinEHFuncInfo & FuncInfo,const MCSymbol * BeginLabel,const MCSymbol * EndLabel,int State)578*9880d681SAndroid Build Coastguard Worker void WinException::emitSEHActionsForRange(const WinEHFuncInfo &FuncInfo,
579*9880d681SAndroid Build Coastguard Worker                                           const MCSymbol *BeginLabel,
580*9880d681SAndroid Build Coastguard Worker                                           const MCSymbol *EndLabel, int State) {
581*9880d681SAndroid Build Coastguard Worker   auto &OS = *Asm->OutStreamer;
582*9880d681SAndroid Build Coastguard Worker   MCContext &Ctx = Asm->OutContext;
583*9880d681SAndroid Build Coastguard Worker 
584*9880d681SAndroid Build Coastguard Worker   bool VerboseAsm = OS.isVerboseAsm();
585*9880d681SAndroid Build Coastguard Worker   auto AddComment = [&](const Twine &Comment) {
586*9880d681SAndroid Build Coastguard Worker     if (VerboseAsm)
587*9880d681SAndroid Build Coastguard Worker       OS.AddComment(Comment);
588*9880d681SAndroid Build Coastguard Worker   };
589*9880d681SAndroid Build Coastguard Worker 
590*9880d681SAndroid Build Coastguard Worker   assert(BeginLabel && EndLabel);
591*9880d681SAndroid Build Coastguard Worker   while (State != -1) {
592*9880d681SAndroid Build Coastguard Worker     const SEHUnwindMapEntry &UME = FuncInfo.SEHUnwindMap[State];
593*9880d681SAndroid Build Coastguard Worker     const MCExpr *FilterOrFinally;
594*9880d681SAndroid Build Coastguard Worker     const MCExpr *ExceptOrNull;
595*9880d681SAndroid Build Coastguard Worker     auto *Handler = UME.Handler.get<MachineBasicBlock *>();
596*9880d681SAndroid Build Coastguard Worker     if (UME.IsFinally) {
597*9880d681SAndroid Build Coastguard Worker       FilterOrFinally = create32bitRef(getMCSymbolForMBB(Asm, Handler));
598*9880d681SAndroid Build Coastguard Worker       ExceptOrNull = MCConstantExpr::create(0, Ctx);
599*9880d681SAndroid Build Coastguard Worker     } else {
600*9880d681SAndroid Build Coastguard Worker       // For an except, the filter can be 1 (catch-all) or a function
601*9880d681SAndroid Build Coastguard Worker       // label.
602*9880d681SAndroid Build Coastguard Worker       FilterOrFinally = UME.Filter ? create32bitRef(UME.Filter)
603*9880d681SAndroid Build Coastguard Worker                                    : MCConstantExpr::create(1, Ctx);
604*9880d681SAndroid Build Coastguard Worker       ExceptOrNull = create32bitRef(Handler->getSymbol());
605*9880d681SAndroid Build Coastguard Worker     }
606*9880d681SAndroid Build Coastguard Worker 
607*9880d681SAndroid Build Coastguard Worker     AddComment("LabelStart");
608*9880d681SAndroid Build Coastguard Worker     OS.EmitValue(getLabelPlusOne(BeginLabel), 4);
609*9880d681SAndroid Build Coastguard Worker     AddComment("LabelEnd");
610*9880d681SAndroid Build Coastguard Worker     OS.EmitValue(getLabelPlusOne(EndLabel), 4);
611*9880d681SAndroid Build Coastguard Worker     AddComment(UME.IsFinally ? "FinallyFunclet" : UME.Filter ? "FilterFunction"
612*9880d681SAndroid Build Coastguard Worker                                                              : "CatchAll");
613*9880d681SAndroid Build Coastguard Worker     OS.EmitValue(FilterOrFinally, 4);
614*9880d681SAndroid Build Coastguard Worker     AddComment(UME.IsFinally ? "Null" : "ExceptionHandler");
615*9880d681SAndroid Build Coastguard Worker     OS.EmitValue(ExceptOrNull, 4);
616*9880d681SAndroid Build Coastguard Worker 
617*9880d681SAndroid Build Coastguard Worker     assert(UME.ToState < State && "states should decrease");
618*9880d681SAndroid Build Coastguard Worker     State = UME.ToState;
619*9880d681SAndroid Build Coastguard Worker   }
620*9880d681SAndroid Build Coastguard Worker }
621*9880d681SAndroid Build Coastguard Worker 
emitCXXFrameHandler3Table(const MachineFunction * MF)622*9880d681SAndroid Build Coastguard Worker void WinException::emitCXXFrameHandler3Table(const MachineFunction *MF) {
623*9880d681SAndroid Build Coastguard Worker   const Function *F = MF->getFunction();
624*9880d681SAndroid Build Coastguard Worker   auto &OS = *Asm->OutStreamer;
625*9880d681SAndroid Build Coastguard Worker   const WinEHFuncInfo &FuncInfo = *MF->getWinEHFuncInfo();
626*9880d681SAndroid Build Coastguard Worker 
627*9880d681SAndroid Build Coastguard Worker   StringRef FuncLinkageName = GlobalValue::getRealLinkageName(F->getName());
628*9880d681SAndroid Build Coastguard Worker 
629*9880d681SAndroid Build Coastguard Worker   SmallVector<std::pair<const MCExpr *, int>, 4> IPToStateTable;
630*9880d681SAndroid Build Coastguard Worker   MCSymbol *FuncInfoXData = nullptr;
631*9880d681SAndroid Build Coastguard Worker   if (shouldEmitPersonality) {
632*9880d681SAndroid Build Coastguard Worker     // If we're 64-bit, emit a pointer to the C++ EH data, and build a map from
633*9880d681SAndroid Build Coastguard Worker     // IPs to state numbers.
634*9880d681SAndroid Build Coastguard Worker     FuncInfoXData =
635*9880d681SAndroid Build Coastguard Worker         Asm->OutContext.getOrCreateSymbol(Twine("$cppxdata$", FuncLinkageName));
636*9880d681SAndroid Build Coastguard Worker     computeIP2StateTable(MF, FuncInfo, IPToStateTable);
637*9880d681SAndroid Build Coastguard Worker   } else {
638*9880d681SAndroid Build Coastguard Worker     FuncInfoXData = Asm->OutContext.getOrCreateLSDASymbol(FuncLinkageName);
639*9880d681SAndroid Build Coastguard Worker   }
640*9880d681SAndroid Build Coastguard Worker 
641*9880d681SAndroid Build Coastguard Worker   int UnwindHelpOffset = 0;
642*9880d681SAndroid Build Coastguard Worker   if (Asm->MAI->usesWindowsCFI())
643*9880d681SAndroid Build Coastguard Worker     UnwindHelpOffset =
644*9880d681SAndroid Build Coastguard Worker         getFrameIndexOffset(FuncInfo.UnwindHelpFrameIdx, FuncInfo);
645*9880d681SAndroid Build Coastguard Worker 
646*9880d681SAndroid Build Coastguard Worker   MCSymbol *UnwindMapXData = nullptr;
647*9880d681SAndroid Build Coastguard Worker   MCSymbol *TryBlockMapXData = nullptr;
648*9880d681SAndroid Build Coastguard Worker   MCSymbol *IPToStateXData = nullptr;
649*9880d681SAndroid Build Coastguard Worker   if (!FuncInfo.CxxUnwindMap.empty())
650*9880d681SAndroid Build Coastguard Worker     UnwindMapXData = Asm->OutContext.getOrCreateSymbol(
651*9880d681SAndroid Build Coastguard Worker         Twine("$stateUnwindMap$", FuncLinkageName));
652*9880d681SAndroid Build Coastguard Worker   if (!FuncInfo.TryBlockMap.empty())
653*9880d681SAndroid Build Coastguard Worker     TryBlockMapXData =
654*9880d681SAndroid Build Coastguard Worker         Asm->OutContext.getOrCreateSymbol(Twine("$tryMap$", FuncLinkageName));
655*9880d681SAndroid Build Coastguard Worker   if (!IPToStateTable.empty())
656*9880d681SAndroid Build Coastguard Worker     IPToStateXData =
657*9880d681SAndroid Build Coastguard Worker         Asm->OutContext.getOrCreateSymbol(Twine("$ip2state$", FuncLinkageName));
658*9880d681SAndroid Build Coastguard Worker 
659*9880d681SAndroid Build Coastguard Worker   bool VerboseAsm = OS.isVerboseAsm();
660*9880d681SAndroid Build Coastguard Worker   auto AddComment = [&](const Twine &Comment) {
661*9880d681SAndroid Build Coastguard Worker     if (VerboseAsm)
662*9880d681SAndroid Build Coastguard Worker       OS.AddComment(Comment);
663*9880d681SAndroid Build Coastguard Worker   };
664*9880d681SAndroid Build Coastguard Worker 
665*9880d681SAndroid Build Coastguard Worker   // FuncInfo {
666*9880d681SAndroid Build Coastguard Worker   //   uint32_t           MagicNumber
667*9880d681SAndroid Build Coastguard Worker   //   int32_t            MaxState;
668*9880d681SAndroid Build Coastguard Worker   //   UnwindMapEntry    *UnwindMap;
669*9880d681SAndroid Build Coastguard Worker   //   uint32_t           NumTryBlocks;
670*9880d681SAndroid Build Coastguard Worker   //   TryBlockMapEntry  *TryBlockMap;
671*9880d681SAndroid Build Coastguard Worker   //   uint32_t           IPMapEntries; // always 0 for x86
672*9880d681SAndroid Build Coastguard Worker   //   IPToStateMapEntry *IPToStateMap; // always 0 for x86
673*9880d681SAndroid Build Coastguard Worker   //   uint32_t           UnwindHelp;   // non-x86 only
674*9880d681SAndroid Build Coastguard Worker   //   ESTypeList        *ESTypeList;
675*9880d681SAndroid Build Coastguard Worker   //   int32_t            EHFlags;
676*9880d681SAndroid Build Coastguard Worker   // }
677*9880d681SAndroid Build Coastguard Worker   // EHFlags & 1 -> Synchronous exceptions only, no async exceptions.
678*9880d681SAndroid Build Coastguard Worker   // EHFlags & 2 -> ???
679*9880d681SAndroid Build Coastguard Worker   // EHFlags & 4 -> The function is noexcept(true), unwinding can't continue.
680*9880d681SAndroid Build Coastguard Worker   OS.EmitValueToAlignment(4);
681*9880d681SAndroid Build Coastguard Worker   OS.EmitLabel(FuncInfoXData);
682*9880d681SAndroid Build Coastguard Worker 
683*9880d681SAndroid Build Coastguard Worker   AddComment("MagicNumber");
684*9880d681SAndroid Build Coastguard Worker   OS.EmitIntValue(0x19930522, 4);
685*9880d681SAndroid Build Coastguard Worker 
686*9880d681SAndroid Build Coastguard Worker   AddComment("MaxState");
687*9880d681SAndroid Build Coastguard Worker   OS.EmitIntValue(FuncInfo.CxxUnwindMap.size(), 4);
688*9880d681SAndroid Build Coastguard Worker 
689*9880d681SAndroid Build Coastguard Worker   AddComment("UnwindMap");
690*9880d681SAndroid Build Coastguard Worker   OS.EmitValue(create32bitRef(UnwindMapXData), 4);
691*9880d681SAndroid Build Coastguard Worker 
692*9880d681SAndroid Build Coastguard Worker   AddComment("NumTryBlocks");
693*9880d681SAndroid Build Coastguard Worker   OS.EmitIntValue(FuncInfo.TryBlockMap.size(), 4);
694*9880d681SAndroid Build Coastguard Worker 
695*9880d681SAndroid Build Coastguard Worker   AddComment("TryBlockMap");
696*9880d681SAndroid Build Coastguard Worker   OS.EmitValue(create32bitRef(TryBlockMapXData), 4);
697*9880d681SAndroid Build Coastguard Worker 
698*9880d681SAndroid Build Coastguard Worker   AddComment("IPMapEntries");
699*9880d681SAndroid Build Coastguard Worker   OS.EmitIntValue(IPToStateTable.size(), 4);
700*9880d681SAndroid Build Coastguard Worker 
701*9880d681SAndroid Build Coastguard Worker   AddComment("IPToStateXData");
702*9880d681SAndroid Build Coastguard Worker   OS.EmitValue(create32bitRef(IPToStateXData), 4);
703*9880d681SAndroid Build Coastguard Worker 
704*9880d681SAndroid Build Coastguard Worker   if (Asm->MAI->usesWindowsCFI()) {
705*9880d681SAndroid Build Coastguard Worker     AddComment("UnwindHelp");
706*9880d681SAndroid Build Coastguard Worker     OS.EmitIntValue(UnwindHelpOffset, 4);
707*9880d681SAndroid Build Coastguard Worker   }
708*9880d681SAndroid Build Coastguard Worker 
709*9880d681SAndroid Build Coastguard Worker   AddComment("ESTypeList");
710*9880d681SAndroid Build Coastguard Worker   OS.EmitIntValue(0, 4);
711*9880d681SAndroid Build Coastguard Worker 
712*9880d681SAndroid Build Coastguard Worker   AddComment("EHFlags");
713*9880d681SAndroid Build Coastguard Worker   OS.EmitIntValue(1, 4);
714*9880d681SAndroid Build Coastguard Worker 
715*9880d681SAndroid Build Coastguard Worker   // UnwindMapEntry {
716*9880d681SAndroid Build Coastguard Worker   //   int32_t ToState;
717*9880d681SAndroid Build Coastguard Worker   //   void  (*Action)();
718*9880d681SAndroid Build Coastguard Worker   // };
719*9880d681SAndroid Build Coastguard Worker   if (UnwindMapXData) {
720*9880d681SAndroid Build Coastguard Worker     OS.EmitLabel(UnwindMapXData);
721*9880d681SAndroid Build Coastguard Worker     for (const CxxUnwindMapEntry &UME : FuncInfo.CxxUnwindMap) {
722*9880d681SAndroid Build Coastguard Worker       MCSymbol *CleanupSym =
723*9880d681SAndroid Build Coastguard Worker           getMCSymbolForMBB(Asm, UME.Cleanup.dyn_cast<MachineBasicBlock *>());
724*9880d681SAndroid Build Coastguard Worker       AddComment("ToState");
725*9880d681SAndroid Build Coastguard Worker       OS.EmitIntValue(UME.ToState, 4);
726*9880d681SAndroid Build Coastguard Worker 
727*9880d681SAndroid Build Coastguard Worker       AddComment("Action");
728*9880d681SAndroid Build Coastguard Worker       OS.EmitValue(create32bitRef(CleanupSym), 4);
729*9880d681SAndroid Build Coastguard Worker     }
730*9880d681SAndroid Build Coastguard Worker   }
731*9880d681SAndroid Build Coastguard Worker 
732*9880d681SAndroid Build Coastguard Worker   // TryBlockMap {
733*9880d681SAndroid Build Coastguard Worker   //   int32_t      TryLow;
734*9880d681SAndroid Build Coastguard Worker   //   int32_t      TryHigh;
735*9880d681SAndroid Build Coastguard Worker   //   int32_t      CatchHigh;
736*9880d681SAndroid Build Coastguard Worker   //   int32_t      NumCatches;
737*9880d681SAndroid Build Coastguard Worker   //   HandlerType *HandlerArray;
738*9880d681SAndroid Build Coastguard Worker   // };
739*9880d681SAndroid Build Coastguard Worker   if (TryBlockMapXData) {
740*9880d681SAndroid Build Coastguard Worker     OS.EmitLabel(TryBlockMapXData);
741*9880d681SAndroid Build Coastguard Worker     SmallVector<MCSymbol *, 1> HandlerMaps;
742*9880d681SAndroid Build Coastguard Worker     for (size_t I = 0, E = FuncInfo.TryBlockMap.size(); I != E; ++I) {
743*9880d681SAndroid Build Coastguard Worker       const WinEHTryBlockMapEntry &TBME = FuncInfo.TryBlockMap[I];
744*9880d681SAndroid Build Coastguard Worker 
745*9880d681SAndroid Build Coastguard Worker       MCSymbol *HandlerMapXData = nullptr;
746*9880d681SAndroid Build Coastguard Worker       if (!TBME.HandlerArray.empty())
747*9880d681SAndroid Build Coastguard Worker         HandlerMapXData =
748*9880d681SAndroid Build Coastguard Worker             Asm->OutContext.getOrCreateSymbol(Twine("$handlerMap$")
749*9880d681SAndroid Build Coastguard Worker                                                   .concat(Twine(I))
750*9880d681SAndroid Build Coastguard Worker                                                   .concat("$")
751*9880d681SAndroid Build Coastguard Worker                                                   .concat(FuncLinkageName));
752*9880d681SAndroid Build Coastguard Worker       HandlerMaps.push_back(HandlerMapXData);
753*9880d681SAndroid Build Coastguard Worker 
754*9880d681SAndroid Build Coastguard Worker       // TBMEs should form intervals.
755*9880d681SAndroid Build Coastguard Worker       assert(0 <= TBME.TryLow && "bad trymap interval");
756*9880d681SAndroid Build Coastguard Worker       assert(TBME.TryLow <= TBME.TryHigh && "bad trymap interval");
757*9880d681SAndroid Build Coastguard Worker       assert(TBME.TryHigh < TBME.CatchHigh && "bad trymap interval");
758*9880d681SAndroid Build Coastguard Worker       assert(TBME.CatchHigh < int(FuncInfo.CxxUnwindMap.size()) &&
759*9880d681SAndroid Build Coastguard Worker              "bad trymap interval");
760*9880d681SAndroid Build Coastguard Worker 
761*9880d681SAndroid Build Coastguard Worker       AddComment("TryLow");
762*9880d681SAndroid Build Coastguard Worker       OS.EmitIntValue(TBME.TryLow, 4);
763*9880d681SAndroid Build Coastguard Worker 
764*9880d681SAndroid Build Coastguard Worker       AddComment("TryHigh");
765*9880d681SAndroid Build Coastguard Worker       OS.EmitIntValue(TBME.TryHigh, 4);
766*9880d681SAndroid Build Coastguard Worker 
767*9880d681SAndroid Build Coastguard Worker       AddComment("CatchHigh");
768*9880d681SAndroid Build Coastguard Worker       OS.EmitIntValue(TBME.CatchHigh, 4);
769*9880d681SAndroid Build Coastguard Worker 
770*9880d681SAndroid Build Coastguard Worker       AddComment("NumCatches");
771*9880d681SAndroid Build Coastguard Worker       OS.EmitIntValue(TBME.HandlerArray.size(), 4);
772*9880d681SAndroid Build Coastguard Worker 
773*9880d681SAndroid Build Coastguard Worker       AddComment("HandlerArray");
774*9880d681SAndroid Build Coastguard Worker       OS.EmitValue(create32bitRef(HandlerMapXData), 4);
775*9880d681SAndroid Build Coastguard Worker     }
776*9880d681SAndroid Build Coastguard Worker 
777*9880d681SAndroid Build Coastguard Worker     // All funclets use the same parent frame offset currently.
778*9880d681SAndroid Build Coastguard Worker     unsigned ParentFrameOffset = 0;
779*9880d681SAndroid Build Coastguard Worker     if (shouldEmitPersonality) {
780*9880d681SAndroid Build Coastguard Worker       const TargetFrameLowering *TFI = MF->getSubtarget().getFrameLowering();
781*9880d681SAndroid Build Coastguard Worker       ParentFrameOffset = TFI->getWinEHParentFrameOffset(*MF);
782*9880d681SAndroid Build Coastguard Worker     }
783*9880d681SAndroid Build Coastguard Worker 
784*9880d681SAndroid Build Coastguard Worker     for (size_t I = 0, E = FuncInfo.TryBlockMap.size(); I != E; ++I) {
785*9880d681SAndroid Build Coastguard Worker       const WinEHTryBlockMapEntry &TBME = FuncInfo.TryBlockMap[I];
786*9880d681SAndroid Build Coastguard Worker       MCSymbol *HandlerMapXData = HandlerMaps[I];
787*9880d681SAndroid Build Coastguard Worker       if (!HandlerMapXData)
788*9880d681SAndroid Build Coastguard Worker         continue;
789*9880d681SAndroid Build Coastguard Worker       // HandlerType {
790*9880d681SAndroid Build Coastguard Worker       //   int32_t         Adjectives;
791*9880d681SAndroid Build Coastguard Worker       //   TypeDescriptor *Type;
792*9880d681SAndroid Build Coastguard Worker       //   int32_t         CatchObjOffset;
793*9880d681SAndroid Build Coastguard Worker       //   void          (*Handler)();
794*9880d681SAndroid Build Coastguard Worker       //   int32_t         ParentFrameOffset; // x64 only
795*9880d681SAndroid Build Coastguard Worker       // };
796*9880d681SAndroid Build Coastguard Worker       OS.EmitLabel(HandlerMapXData);
797*9880d681SAndroid Build Coastguard Worker       for (const WinEHHandlerType &HT : TBME.HandlerArray) {
798*9880d681SAndroid Build Coastguard Worker         // Get the frame escape label with the offset of the catch object. If
799*9880d681SAndroid Build Coastguard Worker         // the index is INT_MAX, then there is no catch object, and we should
800*9880d681SAndroid Build Coastguard Worker         // emit an offset of zero, indicating that no copy will occur.
801*9880d681SAndroid Build Coastguard Worker         const MCExpr *FrameAllocOffsetRef = nullptr;
802*9880d681SAndroid Build Coastguard Worker         if (HT.CatchObj.FrameIndex != INT_MAX) {
803*9880d681SAndroid Build Coastguard Worker           int Offset = getFrameIndexOffset(HT.CatchObj.FrameIndex, FuncInfo);
804*9880d681SAndroid Build Coastguard Worker           assert(Offset != 0 && "Illegal offset for catch object!");
805*9880d681SAndroid Build Coastguard Worker           FrameAllocOffsetRef = MCConstantExpr::create(Offset, Asm->OutContext);
806*9880d681SAndroid Build Coastguard Worker         } else {
807*9880d681SAndroid Build Coastguard Worker           FrameAllocOffsetRef = MCConstantExpr::create(0, Asm->OutContext);
808*9880d681SAndroid Build Coastguard Worker         }
809*9880d681SAndroid Build Coastguard Worker 
810*9880d681SAndroid Build Coastguard Worker         MCSymbol *HandlerSym =
811*9880d681SAndroid Build Coastguard Worker             getMCSymbolForMBB(Asm, HT.Handler.dyn_cast<MachineBasicBlock *>());
812*9880d681SAndroid Build Coastguard Worker 
813*9880d681SAndroid Build Coastguard Worker         AddComment("Adjectives");
814*9880d681SAndroid Build Coastguard Worker         OS.EmitIntValue(HT.Adjectives, 4);
815*9880d681SAndroid Build Coastguard Worker 
816*9880d681SAndroid Build Coastguard Worker         AddComment("Type");
817*9880d681SAndroid Build Coastguard Worker         OS.EmitValue(create32bitRef(HT.TypeDescriptor), 4);
818*9880d681SAndroid Build Coastguard Worker 
819*9880d681SAndroid Build Coastguard Worker         AddComment("CatchObjOffset");
820*9880d681SAndroid Build Coastguard Worker         OS.EmitValue(FrameAllocOffsetRef, 4);
821*9880d681SAndroid Build Coastguard Worker 
822*9880d681SAndroid Build Coastguard Worker         AddComment("Handler");
823*9880d681SAndroid Build Coastguard Worker         OS.EmitValue(create32bitRef(HandlerSym), 4);
824*9880d681SAndroid Build Coastguard Worker 
825*9880d681SAndroid Build Coastguard Worker         if (shouldEmitPersonality) {
826*9880d681SAndroid Build Coastguard Worker           AddComment("ParentFrameOffset");
827*9880d681SAndroid Build Coastguard Worker           OS.EmitIntValue(ParentFrameOffset, 4);
828*9880d681SAndroid Build Coastguard Worker         }
829*9880d681SAndroid Build Coastguard Worker       }
830*9880d681SAndroid Build Coastguard Worker     }
831*9880d681SAndroid Build Coastguard Worker   }
832*9880d681SAndroid Build Coastguard Worker 
833*9880d681SAndroid Build Coastguard Worker   // IPToStateMapEntry {
834*9880d681SAndroid Build Coastguard Worker   //   void   *IP;
835*9880d681SAndroid Build Coastguard Worker   //   int32_t State;
836*9880d681SAndroid Build Coastguard Worker   // };
837*9880d681SAndroid Build Coastguard Worker   if (IPToStateXData) {
838*9880d681SAndroid Build Coastguard Worker     OS.EmitLabel(IPToStateXData);
839*9880d681SAndroid Build Coastguard Worker     for (auto &IPStatePair : IPToStateTable) {
840*9880d681SAndroid Build Coastguard Worker       AddComment("IP");
841*9880d681SAndroid Build Coastguard Worker       OS.EmitValue(IPStatePair.first, 4);
842*9880d681SAndroid Build Coastguard Worker       AddComment("ToState");
843*9880d681SAndroid Build Coastguard Worker       OS.EmitIntValue(IPStatePair.second, 4);
844*9880d681SAndroid Build Coastguard Worker     }
845*9880d681SAndroid Build Coastguard Worker   }
846*9880d681SAndroid Build Coastguard Worker }
847*9880d681SAndroid Build Coastguard Worker 
computeIP2StateTable(const MachineFunction * MF,const WinEHFuncInfo & FuncInfo,SmallVectorImpl<std::pair<const MCExpr *,int>> & IPToStateTable)848*9880d681SAndroid Build Coastguard Worker void WinException::computeIP2StateTable(
849*9880d681SAndroid Build Coastguard Worker     const MachineFunction *MF, const WinEHFuncInfo &FuncInfo,
850*9880d681SAndroid Build Coastguard Worker     SmallVectorImpl<std::pair<const MCExpr *, int>> &IPToStateTable) {
851*9880d681SAndroid Build Coastguard Worker 
852*9880d681SAndroid Build Coastguard Worker   for (MachineFunction::const_iterator FuncletStart = MF->begin(),
853*9880d681SAndroid Build Coastguard Worker                                        FuncletEnd = MF->begin(),
854*9880d681SAndroid Build Coastguard Worker                                        End = MF->end();
855*9880d681SAndroid Build Coastguard Worker        FuncletStart != End; FuncletStart = FuncletEnd) {
856*9880d681SAndroid Build Coastguard Worker     // Find the end of the funclet
857*9880d681SAndroid Build Coastguard Worker     while (++FuncletEnd != End) {
858*9880d681SAndroid Build Coastguard Worker       if (FuncletEnd->isEHFuncletEntry()) {
859*9880d681SAndroid Build Coastguard Worker         break;
860*9880d681SAndroid Build Coastguard Worker       }
861*9880d681SAndroid Build Coastguard Worker     }
862*9880d681SAndroid Build Coastguard Worker 
863*9880d681SAndroid Build Coastguard Worker     // Don't emit ip2state entries for cleanup funclets. Any interesting
864*9880d681SAndroid Build Coastguard Worker     // exceptional actions in cleanups must be handled in a separate IR
865*9880d681SAndroid Build Coastguard Worker     // function.
866*9880d681SAndroid Build Coastguard Worker     if (FuncletStart->isCleanupFuncletEntry())
867*9880d681SAndroid Build Coastguard Worker       continue;
868*9880d681SAndroid Build Coastguard Worker 
869*9880d681SAndroid Build Coastguard Worker     MCSymbol *StartLabel;
870*9880d681SAndroid Build Coastguard Worker     int BaseState;
871*9880d681SAndroid Build Coastguard Worker     if (FuncletStart == MF->begin()) {
872*9880d681SAndroid Build Coastguard Worker       BaseState = NullState;
873*9880d681SAndroid Build Coastguard Worker       StartLabel = Asm->getFunctionBegin();
874*9880d681SAndroid Build Coastguard Worker     } else {
875*9880d681SAndroid Build Coastguard Worker       auto *FuncletPad =
876*9880d681SAndroid Build Coastguard Worker           cast<FuncletPadInst>(FuncletStart->getBasicBlock()->getFirstNonPHI());
877*9880d681SAndroid Build Coastguard Worker       assert(FuncInfo.FuncletBaseStateMap.count(FuncletPad) != 0);
878*9880d681SAndroid Build Coastguard Worker       BaseState = FuncInfo.FuncletBaseStateMap.find(FuncletPad)->second;
879*9880d681SAndroid Build Coastguard Worker       StartLabel = getMCSymbolForMBB(Asm, &*FuncletStart);
880*9880d681SAndroid Build Coastguard Worker     }
881*9880d681SAndroid Build Coastguard Worker     assert(StartLabel && "need local function start label");
882*9880d681SAndroid Build Coastguard Worker     IPToStateTable.push_back(
883*9880d681SAndroid Build Coastguard Worker         std::make_pair(create32bitRef(StartLabel), BaseState));
884*9880d681SAndroid Build Coastguard Worker 
885*9880d681SAndroid Build Coastguard Worker     for (const auto &StateChange : InvokeStateChangeIterator::range(
886*9880d681SAndroid Build Coastguard Worker              FuncInfo, FuncletStart, FuncletEnd, BaseState)) {
887*9880d681SAndroid Build Coastguard Worker       // Compute the label to report as the start of this entry; use the EH
888*9880d681SAndroid Build Coastguard Worker       // start label for the invoke if we have one, otherwise (this is a call
889*9880d681SAndroid Build Coastguard Worker       // which may unwind to our caller and does not have an EH start label, so)
890*9880d681SAndroid Build Coastguard Worker       // use the previous end label.
891*9880d681SAndroid Build Coastguard Worker       const MCSymbol *ChangeLabel = StateChange.NewStartLabel;
892*9880d681SAndroid Build Coastguard Worker       if (!ChangeLabel)
893*9880d681SAndroid Build Coastguard Worker         ChangeLabel = StateChange.PreviousEndLabel;
894*9880d681SAndroid Build Coastguard Worker       // Emit an entry indicating that PCs after 'Label' have this EH state.
895*9880d681SAndroid Build Coastguard Worker       IPToStateTable.push_back(
896*9880d681SAndroid Build Coastguard Worker           std::make_pair(getLabelPlusOne(ChangeLabel), StateChange.NewState));
897*9880d681SAndroid Build Coastguard Worker       // FIXME: assert that NewState is between CatchLow and CatchHigh.
898*9880d681SAndroid Build Coastguard Worker     }
899*9880d681SAndroid Build Coastguard Worker   }
900*9880d681SAndroid Build Coastguard Worker }
901*9880d681SAndroid Build Coastguard Worker 
emitEHRegistrationOffsetLabel(const WinEHFuncInfo & FuncInfo,StringRef FLinkageName)902*9880d681SAndroid Build Coastguard Worker void WinException::emitEHRegistrationOffsetLabel(const WinEHFuncInfo &FuncInfo,
903*9880d681SAndroid Build Coastguard Worker                                                  StringRef FLinkageName) {
904*9880d681SAndroid Build Coastguard Worker   // Outlined helpers called by the EH runtime need to know the offset of the EH
905*9880d681SAndroid Build Coastguard Worker   // registration in order to recover the parent frame pointer. Now that we know
906*9880d681SAndroid Build Coastguard Worker   // we've code generated the parent, we can emit the label assignment that
907*9880d681SAndroid Build Coastguard Worker   // those helpers use to get the offset of the registration node.
908*9880d681SAndroid Build Coastguard Worker   MCContext &Ctx = Asm->OutContext;
909*9880d681SAndroid Build Coastguard Worker   MCSymbol *ParentFrameOffset =
910*9880d681SAndroid Build Coastguard Worker       Ctx.getOrCreateParentFrameOffsetSymbol(FLinkageName);
911*9880d681SAndroid Build Coastguard Worker   unsigned UnusedReg;
912*9880d681SAndroid Build Coastguard Worker   const TargetFrameLowering *TFI = Asm->MF->getSubtarget().getFrameLowering();
913*9880d681SAndroid Build Coastguard Worker   int64_t Offset = TFI->getFrameIndexReference(
914*9880d681SAndroid Build Coastguard Worker       *Asm->MF, FuncInfo.EHRegNodeFrameIndex, UnusedReg);
915*9880d681SAndroid Build Coastguard Worker   const MCExpr *MCOffset = MCConstantExpr::create(Offset, Ctx);
916*9880d681SAndroid Build Coastguard Worker   Asm->OutStreamer->EmitAssignment(ParentFrameOffset, MCOffset);
917*9880d681SAndroid Build Coastguard Worker }
918*9880d681SAndroid Build Coastguard Worker 
919*9880d681SAndroid Build Coastguard Worker /// Emit the language-specific data that _except_handler3 and 4 expect. This is
920*9880d681SAndroid Build Coastguard Worker /// functionally equivalent to the __C_specific_handler table, except it is
921*9880d681SAndroid Build Coastguard Worker /// indexed by state number instead of IP.
emitExceptHandlerTable(const MachineFunction * MF)922*9880d681SAndroid Build Coastguard Worker void WinException::emitExceptHandlerTable(const MachineFunction *MF) {
923*9880d681SAndroid Build Coastguard Worker   MCStreamer &OS = *Asm->OutStreamer;
924*9880d681SAndroid Build Coastguard Worker   const Function *F = MF->getFunction();
925*9880d681SAndroid Build Coastguard Worker   StringRef FLinkageName = GlobalValue::getRealLinkageName(F->getName());
926*9880d681SAndroid Build Coastguard Worker 
927*9880d681SAndroid Build Coastguard Worker   bool VerboseAsm = OS.isVerboseAsm();
928*9880d681SAndroid Build Coastguard Worker   auto AddComment = [&](const Twine &Comment) {
929*9880d681SAndroid Build Coastguard Worker     if (VerboseAsm)
930*9880d681SAndroid Build Coastguard Worker       OS.AddComment(Comment);
931*9880d681SAndroid Build Coastguard Worker   };
932*9880d681SAndroid Build Coastguard Worker 
933*9880d681SAndroid Build Coastguard Worker   const WinEHFuncInfo &FuncInfo = *MF->getWinEHFuncInfo();
934*9880d681SAndroid Build Coastguard Worker   emitEHRegistrationOffsetLabel(FuncInfo, FLinkageName);
935*9880d681SAndroid Build Coastguard Worker 
936*9880d681SAndroid Build Coastguard Worker   // Emit the __ehtable label that we use for llvm.x86.seh.lsda.
937*9880d681SAndroid Build Coastguard Worker   MCSymbol *LSDALabel = Asm->OutContext.getOrCreateLSDASymbol(FLinkageName);
938*9880d681SAndroid Build Coastguard Worker   OS.EmitValueToAlignment(4);
939*9880d681SAndroid Build Coastguard Worker   OS.EmitLabel(LSDALabel);
940*9880d681SAndroid Build Coastguard Worker 
941*9880d681SAndroid Build Coastguard Worker   const Function *Per =
942*9880d681SAndroid Build Coastguard Worker       dyn_cast<Function>(F->getPersonalityFn()->stripPointerCasts());
943*9880d681SAndroid Build Coastguard Worker   StringRef PerName = Per->getName();
944*9880d681SAndroid Build Coastguard Worker   int BaseState = -1;
945*9880d681SAndroid Build Coastguard Worker   if (PerName == "_except_handler4") {
946*9880d681SAndroid Build Coastguard Worker     // The LSDA for _except_handler4 starts with this struct, followed by the
947*9880d681SAndroid Build Coastguard Worker     // scope table:
948*9880d681SAndroid Build Coastguard Worker     //
949*9880d681SAndroid Build Coastguard Worker     // struct EH4ScopeTable {
950*9880d681SAndroid Build Coastguard Worker     //   int32_t GSCookieOffset;
951*9880d681SAndroid Build Coastguard Worker     //   int32_t GSCookieXOROffset;
952*9880d681SAndroid Build Coastguard Worker     //   int32_t EHCookieOffset;
953*9880d681SAndroid Build Coastguard Worker     //   int32_t EHCookieXOROffset;
954*9880d681SAndroid Build Coastguard Worker     //   ScopeTableEntry ScopeRecord[];
955*9880d681SAndroid Build Coastguard Worker     // };
956*9880d681SAndroid Build Coastguard Worker     //
957*9880d681SAndroid Build Coastguard Worker     // Offsets are %ebp relative.
958*9880d681SAndroid Build Coastguard Worker     //
959*9880d681SAndroid Build Coastguard Worker     // The GS cookie is present only if the function needs stack protection.
960*9880d681SAndroid Build Coastguard Worker     // GSCookieOffset = -2 means that GS cookie is not used.
961*9880d681SAndroid Build Coastguard Worker     //
962*9880d681SAndroid Build Coastguard Worker     // The EH cookie is always present.
963*9880d681SAndroid Build Coastguard Worker     //
964*9880d681SAndroid Build Coastguard Worker     // Check is done the following way:
965*9880d681SAndroid Build Coastguard Worker     //    (ebp+CookieXOROffset) ^ [ebp+CookieOffset] == _security_cookie
966*9880d681SAndroid Build Coastguard Worker 
967*9880d681SAndroid Build Coastguard Worker     // Retrieve the Guard Stack slot.
968*9880d681SAndroid Build Coastguard Worker     int GSCookieOffset = -2;
969*9880d681SAndroid Build Coastguard Worker     const MachineFrameInfo *MFI = MF->getFrameInfo();
970*9880d681SAndroid Build Coastguard Worker     if (MFI->hasStackProtectorIndex()) {
971*9880d681SAndroid Build Coastguard Worker       unsigned UnusedReg;
972*9880d681SAndroid Build Coastguard Worker       const TargetFrameLowering *TFI = MF->getSubtarget().getFrameLowering();
973*9880d681SAndroid Build Coastguard Worker       int SSPIdx = MFI->getStackProtectorIndex();
974*9880d681SAndroid Build Coastguard Worker       GSCookieOffset = TFI->getFrameIndexReference(*MF, SSPIdx, UnusedReg);
975*9880d681SAndroid Build Coastguard Worker     }
976*9880d681SAndroid Build Coastguard Worker 
977*9880d681SAndroid Build Coastguard Worker     // Retrieve the EH Guard slot.
978*9880d681SAndroid Build Coastguard Worker     // TODO(etienneb): Get rid of this value and change it for and assertion.
979*9880d681SAndroid Build Coastguard Worker     int EHCookieOffset = 9999;
980*9880d681SAndroid Build Coastguard Worker     if (FuncInfo.EHGuardFrameIndex != INT_MAX) {
981*9880d681SAndroid Build Coastguard Worker       unsigned UnusedReg;
982*9880d681SAndroid Build Coastguard Worker       const TargetFrameLowering *TFI = MF->getSubtarget().getFrameLowering();
983*9880d681SAndroid Build Coastguard Worker       int EHGuardIdx = FuncInfo.EHGuardFrameIndex;
984*9880d681SAndroid Build Coastguard Worker       EHCookieOffset = TFI->getFrameIndexReference(*MF, EHGuardIdx, UnusedReg);
985*9880d681SAndroid Build Coastguard Worker     }
986*9880d681SAndroid Build Coastguard Worker 
987*9880d681SAndroid Build Coastguard Worker     AddComment("GSCookieOffset");
988*9880d681SAndroid Build Coastguard Worker     OS.EmitIntValue(GSCookieOffset, 4);
989*9880d681SAndroid Build Coastguard Worker     AddComment("GSCookieXOROffset");
990*9880d681SAndroid Build Coastguard Worker     OS.EmitIntValue(0, 4);
991*9880d681SAndroid Build Coastguard Worker     AddComment("EHCookieOffset");
992*9880d681SAndroid Build Coastguard Worker     OS.EmitIntValue(EHCookieOffset, 4);
993*9880d681SAndroid Build Coastguard Worker     AddComment("EHCookieXOROffset");
994*9880d681SAndroid Build Coastguard Worker     OS.EmitIntValue(0, 4);
995*9880d681SAndroid Build Coastguard Worker     BaseState = -2;
996*9880d681SAndroid Build Coastguard Worker   }
997*9880d681SAndroid Build Coastguard Worker 
998*9880d681SAndroid Build Coastguard Worker   assert(!FuncInfo.SEHUnwindMap.empty());
999*9880d681SAndroid Build Coastguard Worker   for (const SEHUnwindMapEntry &UME : FuncInfo.SEHUnwindMap) {
1000*9880d681SAndroid Build Coastguard Worker     auto *Handler = UME.Handler.get<MachineBasicBlock *>();
1001*9880d681SAndroid Build Coastguard Worker     const MCSymbol *ExceptOrFinally =
1002*9880d681SAndroid Build Coastguard Worker         UME.IsFinally ? getMCSymbolForMBB(Asm, Handler) : Handler->getSymbol();
1003*9880d681SAndroid Build Coastguard Worker     // -1 is usually the base state for "unwind to caller", but for
1004*9880d681SAndroid Build Coastguard Worker     // _except_handler4 it's -2. Do that replacement here if necessary.
1005*9880d681SAndroid Build Coastguard Worker     int ToState = UME.ToState == -1 ? BaseState : UME.ToState;
1006*9880d681SAndroid Build Coastguard Worker     AddComment("ToState");
1007*9880d681SAndroid Build Coastguard Worker     OS.EmitIntValue(ToState, 4);
1008*9880d681SAndroid Build Coastguard Worker     AddComment(UME.IsFinally ? "Null" : "FilterFunction");
1009*9880d681SAndroid Build Coastguard Worker     OS.EmitValue(create32bitRef(UME.Filter), 4);
1010*9880d681SAndroid Build Coastguard Worker     AddComment(UME.IsFinally ? "FinallyFunclet" : "ExceptionHandler");
1011*9880d681SAndroid Build Coastguard Worker     OS.EmitValue(create32bitRef(ExceptOrFinally), 4);
1012*9880d681SAndroid Build Coastguard Worker   }
1013*9880d681SAndroid Build Coastguard Worker }
1014*9880d681SAndroid Build Coastguard Worker 
getTryRank(const WinEHFuncInfo & FuncInfo,int State)1015*9880d681SAndroid Build Coastguard Worker static int getTryRank(const WinEHFuncInfo &FuncInfo, int State) {
1016*9880d681SAndroid Build Coastguard Worker   int Rank = 0;
1017*9880d681SAndroid Build Coastguard Worker   while (State != -1) {
1018*9880d681SAndroid Build Coastguard Worker     ++Rank;
1019*9880d681SAndroid Build Coastguard Worker     State = FuncInfo.ClrEHUnwindMap[State].TryParentState;
1020*9880d681SAndroid Build Coastguard Worker   }
1021*9880d681SAndroid Build Coastguard Worker   return Rank;
1022*9880d681SAndroid Build Coastguard Worker }
1023*9880d681SAndroid Build Coastguard Worker 
getTryAncestor(const WinEHFuncInfo & FuncInfo,int Left,int Right)1024*9880d681SAndroid Build Coastguard Worker static int getTryAncestor(const WinEHFuncInfo &FuncInfo, int Left, int Right) {
1025*9880d681SAndroid Build Coastguard Worker   int LeftRank = getTryRank(FuncInfo, Left);
1026*9880d681SAndroid Build Coastguard Worker   int RightRank = getTryRank(FuncInfo, Right);
1027*9880d681SAndroid Build Coastguard Worker 
1028*9880d681SAndroid Build Coastguard Worker   while (LeftRank < RightRank) {
1029*9880d681SAndroid Build Coastguard Worker     Right = FuncInfo.ClrEHUnwindMap[Right].TryParentState;
1030*9880d681SAndroid Build Coastguard Worker     --RightRank;
1031*9880d681SAndroid Build Coastguard Worker   }
1032*9880d681SAndroid Build Coastguard Worker 
1033*9880d681SAndroid Build Coastguard Worker   while (RightRank < LeftRank) {
1034*9880d681SAndroid Build Coastguard Worker     Left = FuncInfo.ClrEHUnwindMap[Left].TryParentState;
1035*9880d681SAndroid Build Coastguard Worker     --LeftRank;
1036*9880d681SAndroid Build Coastguard Worker   }
1037*9880d681SAndroid Build Coastguard Worker 
1038*9880d681SAndroid Build Coastguard Worker   while (Left != Right) {
1039*9880d681SAndroid Build Coastguard Worker     Left = FuncInfo.ClrEHUnwindMap[Left].TryParentState;
1040*9880d681SAndroid Build Coastguard Worker     Right = FuncInfo.ClrEHUnwindMap[Right].TryParentState;
1041*9880d681SAndroid Build Coastguard Worker   }
1042*9880d681SAndroid Build Coastguard Worker 
1043*9880d681SAndroid Build Coastguard Worker   return Left;
1044*9880d681SAndroid Build Coastguard Worker }
1045*9880d681SAndroid Build Coastguard Worker 
emitCLRExceptionTable(const MachineFunction * MF)1046*9880d681SAndroid Build Coastguard Worker void WinException::emitCLRExceptionTable(const MachineFunction *MF) {
1047*9880d681SAndroid Build Coastguard Worker   // CLR EH "states" are really just IDs that identify handlers/funclets;
1048*9880d681SAndroid Build Coastguard Worker   // states, handlers, and funclets all have 1:1 mappings between them, and a
1049*9880d681SAndroid Build Coastguard Worker   // handler/funclet's "state" is its index in the ClrEHUnwindMap.
1050*9880d681SAndroid Build Coastguard Worker   MCStreamer &OS = *Asm->OutStreamer;
1051*9880d681SAndroid Build Coastguard Worker   const WinEHFuncInfo &FuncInfo = *MF->getWinEHFuncInfo();
1052*9880d681SAndroid Build Coastguard Worker   MCSymbol *FuncBeginSym = Asm->getFunctionBegin();
1053*9880d681SAndroid Build Coastguard Worker   MCSymbol *FuncEndSym = Asm->getFunctionEnd();
1054*9880d681SAndroid Build Coastguard Worker 
1055*9880d681SAndroid Build Coastguard Worker   // A ClrClause describes a protected region.
1056*9880d681SAndroid Build Coastguard Worker   struct ClrClause {
1057*9880d681SAndroid Build Coastguard Worker     const MCSymbol *StartLabel; // Start of protected region
1058*9880d681SAndroid Build Coastguard Worker     const MCSymbol *EndLabel;   // End of protected region
1059*9880d681SAndroid Build Coastguard Worker     int State;          // Index of handler protecting the protected region
1060*9880d681SAndroid Build Coastguard Worker     int EnclosingState; // Index of funclet enclosing the protected region
1061*9880d681SAndroid Build Coastguard Worker   };
1062*9880d681SAndroid Build Coastguard Worker   SmallVector<ClrClause, 8> Clauses;
1063*9880d681SAndroid Build Coastguard Worker 
1064*9880d681SAndroid Build Coastguard Worker   // Build a map from handler MBBs to their corresponding states (i.e. their
1065*9880d681SAndroid Build Coastguard Worker   // indices in the ClrEHUnwindMap).
1066*9880d681SAndroid Build Coastguard Worker   int NumStates = FuncInfo.ClrEHUnwindMap.size();
1067*9880d681SAndroid Build Coastguard Worker   assert(NumStates > 0 && "Don't need exception table!");
1068*9880d681SAndroid Build Coastguard Worker   DenseMap<const MachineBasicBlock *, int> HandlerStates;
1069*9880d681SAndroid Build Coastguard Worker   for (int State = 0; State < NumStates; ++State) {
1070*9880d681SAndroid Build Coastguard Worker     MachineBasicBlock *HandlerBlock =
1071*9880d681SAndroid Build Coastguard Worker         FuncInfo.ClrEHUnwindMap[State].Handler.get<MachineBasicBlock *>();
1072*9880d681SAndroid Build Coastguard Worker     HandlerStates[HandlerBlock] = State;
1073*9880d681SAndroid Build Coastguard Worker     // Use this loop through all handlers to verify our assumption (used in
1074*9880d681SAndroid Build Coastguard Worker     // the MinEnclosingState computation) that enclosing funclets have lower
1075*9880d681SAndroid Build Coastguard Worker     // state numbers than their enclosed funclets.
1076*9880d681SAndroid Build Coastguard Worker     assert(FuncInfo.ClrEHUnwindMap[State].HandlerParentState < State &&
1077*9880d681SAndroid Build Coastguard Worker            "ill-formed state numbering");
1078*9880d681SAndroid Build Coastguard Worker   }
1079*9880d681SAndroid Build Coastguard Worker   // Map the main function to the NullState.
1080*9880d681SAndroid Build Coastguard Worker   HandlerStates[&MF->front()] = NullState;
1081*9880d681SAndroid Build Coastguard Worker 
1082*9880d681SAndroid Build Coastguard Worker   // Write out a sentinel indicating the end of the standard (Windows) xdata
1083*9880d681SAndroid Build Coastguard Worker   // and the start of the additional (CLR) info.
1084*9880d681SAndroid Build Coastguard Worker   OS.EmitIntValue(0xffffffff, 4);
1085*9880d681SAndroid Build Coastguard Worker   // Write out the number of funclets
1086*9880d681SAndroid Build Coastguard Worker   OS.EmitIntValue(NumStates, 4);
1087*9880d681SAndroid Build Coastguard Worker 
1088*9880d681SAndroid Build Coastguard Worker   // Walk the machine blocks/instrs, computing and emitting a few things:
1089*9880d681SAndroid Build Coastguard Worker   // 1. Emit a list of the offsets to each handler entry, in lexical order.
1090*9880d681SAndroid Build Coastguard Worker   // 2. Compute a map (EndSymbolMap) from each funclet to the symbol at its end.
1091*9880d681SAndroid Build Coastguard Worker   // 3. Compute the list of ClrClauses, in the required order (inner before
1092*9880d681SAndroid Build Coastguard Worker   //    outer, earlier before later; the order by which a forward scan with
1093*9880d681SAndroid Build Coastguard Worker   //    early termination will find the innermost enclosing clause covering
1094*9880d681SAndroid Build Coastguard Worker   //    a given address).
1095*9880d681SAndroid Build Coastguard Worker   // 4. A map (MinClauseMap) from each handler index to the index of the
1096*9880d681SAndroid Build Coastguard Worker   //    outermost funclet/function which contains a try clause targeting the
1097*9880d681SAndroid Build Coastguard Worker   //    key handler.  This will be used to determine IsDuplicate-ness when
1098*9880d681SAndroid Build Coastguard Worker   //    emitting ClrClauses.  The NullState value is used to indicate that the
1099*9880d681SAndroid Build Coastguard Worker   //    top-level function contains a try clause targeting the key handler.
1100*9880d681SAndroid Build Coastguard Worker   // HandlerStack is a stack of (PendingStartLabel, PendingState) pairs for
1101*9880d681SAndroid Build Coastguard Worker   // try regions we entered before entering the PendingState try but which
1102*9880d681SAndroid Build Coastguard Worker   // we haven't yet exited.
1103*9880d681SAndroid Build Coastguard Worker   SmallVector<std::pair<const MCSymbol *, int>, 4> HandlerStack;
1104*9880d681SAndroid Build Coastguard Worker   // EndSymbolMap and MinClauseMap are maps described above.
1105*9880d681SAndroid Build Coastguard Worker   std::unique_ptr<MCSymbol *[]> EndSymbolMap(new MCSymbol *[NumStates]);
1106*9880d681SAndroid Build Coastguard Worker   SmallVector<int, 4> MinClauseMap((size_t)NumStates, NumStates);
1107*9880d681SAndroid Build Coastguard Worker 
1108*9880d681SAndroid Build Coastguard Worker   // Visit the root function and each funclet.
1109*9880d681SAndroid Build Coastguard Worker   for (MachineFunction::const_iterator FuncletStart = MF->begin(),
1110*9880d681SAndroid Build Coastguard Worker                                        FuncletEnd = MF->begin(),
1111*9880d681SAndroid Build Coastguard Worker                                        End = MF->end();
1112*9880d681SAndroid Build Coastguard Worker        FuncletStart != End; FuncletStart = FuncletEnd) {
1113*9880d681SAndroid Build Coastguard Worker     int FuncletState = HandlerStates[&*FuncletStart];
1114*9880d681SAndroid Build Coastguard Worker     // Find the end of the funclet
1115*9880d681SAndroid Build Coastguard Worker     MCSymbol *EndSymbol = FuncEndSym;
1116*9880d681SAndroid Build Coastguard Worker     while (++FuncletEnd != End) {
1117*9880d681SAndroid Build Coastguard Worker       if (FuncletEnd->isEHFuncletEntry()) {
1118*9880d681SAndroid Build Coastguard Worker         EndSymbol = getMCSymbolForMBB(Asm, &*FuncletEnd);
1119*9880d681SAndroid Build Coastguard Worker         break;
1120*9880d681SAndroid Build Coastguard Worker       }
1121*9880d681SAndroid Build Coastguard Worker     }
1122*9880d681SAndroid Build Coastguard Worker     // Emit the function/funclet end and, if this is a funclet (and not the
1123*9880d681SAndroid Build Coastguard Worker     // root function), record it in the EndSymbolMap.
1124*9880d681SAndroid Build Coastguard Worker     OS.EmitValue(getOffset(EndSymbol, FuncBeginSym), 4);
1125*9880d681SAndroid Build Coastguard Worker     if (FuncletState != NullState) {
1126*9880d681SAndroid Build Coastguard Worker       // Record the end of the handler.
1127*9880d681SAndroid Build Coastguard Worker       EndSymbolMap[FuncletState] = EndSymbol;
1128*9880d681SAndroid Build Coastguard Worker     }
1129*9880d681SAndroid Build Coastguard Worker 
1130*9880d681SAndroid Build Coastguard Worker     // Walk the state changes in this function/funclet and compute its clauses.
1131*9880d681SAndroid Build Coastguard Worker     // Funclets always start in the null state.
1132*9880d681SAndroid Build Coastguard Worker     const MCSymbol *CurrentStartLabel = nullptr;
1133*9880d681SAndroid Build Coastguard Worker     int CurrentState = NullState;
1134*9880d681SAndroid Build Coastguard Worker     assert(HandlerStack.empty());
1135*9880d681SAndroid Build Coastguard Worker     for (const auto &StateChange :
1136*9880d681SAndroid Build Coastguard Worker          InvokeStateChangeIterator::range(FuncInfo, FuncletStart, FuncletEnd)) {
1137*9880d681SAndroid Build Coastguard Worker       // Close any try regions we're not still under
1138*9880d681SAndroid Build Coastguard Worker       int StillPendingState =
1139*9880d681SAndroid Build Coastguard Worker           getTryAncestor(FuncInfo, CurrentState, StateChange.NewState);
1140*9880d681SAndroid Build Coastguard Worker       while (CurrentState != StillPendingState) {
1141*9880d681SAndroid Build Coastguard Worker         assert(CurrentState != NullState &&
1142*9880d681SAndroid Build Coastguard Worker                "Failed to find still-pending state!");
1143*9880d681SAndroid Build Coastguard Worker         // Close the pending clause
1144*9880d681SAndroid Build Coastguard Worker         Clauses.push_back({CurrentStartLabel, StateChange.PreviousEndLabel,
1145*9880d681SAndroid Build Coastguard Worker                            CurrentState, FuncletState});
1146*9880d681SAndroid Build Coastguard Worker         // Now the next-outer try region is current
1147*9880d681SAndroid Build Coastguard Worker         CurrentState = FuncInfo.ClrEHUnwindMap[CurrentState].TryParentState;
1148*9880d681SAndroid Build Coastguard Worker         // Pop the new start label from the handler stack if we've exited all
1149*9880d681SAndroid Build Coastguard Worker         // inner try regions of the corresponding try region.
1150*9880d681SAndroid Build Coastguard Worker         if (HandlerStack.back().second == CurrentState)
1151*9880d681SAndroid Build Coastguard Worker           CurrentStartLabel = HandlerStack.pop_back_val().first;
1152*9880d681SAndroid Build Coastguard Worker       }
1153*9880d681SAndroid Build Coastguard Worker 
1154*9880d681SAndroid Build Coastguard Worker       if (StateChange.NewState != CurrentState) {
1155*9880d681SAndroid Build Coastguard Worker         // For each clause we're starting, update the MinClauseMap so we can
1156*9880d681SAndroid Build Coastguard Worker         // know which is the topmost funclet containing a clause targeting
1157*9880d681SAndroid Build Coastguard Worker         // it.
1158*9880d681SAndroid Build Coastguard Worker         for (int EnteredState = StateChange.NewState;
1159*9880d681SAndroid Build Coastguard Worker              EnteredState != CurrentState;
1160*9880d681SAndroid Build Coastguard Worker              EnteredState =
1161*9880d681SAndroid Build Coastguard Worker                  FuncInfo.ClrEHUnwindMap[EnteredState].TryParentState) {
1162*9880d681SAndroid Build Coastguard Worker           int &MinEnclosingState = MinClauseMap[EnteredState];
1163*9880d681SAndroid Build Coastguard Worker           if (FuncletState < MinEnclosingState)
1164*9880d681SAndroid Build Coastguard Worker             MinEnclosingState = FuncletState;
1165*9880d681SAndroid Build Coastguard Worker         }
1166*9880d681SAndroid Build Coastguard Worker         // Save the previous current start/label on the stack and update to
1167*9880d681SAndroid Build Coastguard Worker         // the newly-current start/state.
1168*9880d681SAndroid Build Coastguard Worker         HandlerStack.emplace_back(CurrentStartLabel, CurrentState);
1169*9880d681SAndroid Build Coastguard Worker         CurrentStartLabel = StateChange.NewStartLabel;
1170*9880d681SAndroid Build Coastguard Worker         CurrentState = StateChange.NewState;
1171*9880d681SAndroid Build Coastguard Worker       }
1172*9880d681SAndroid Build Coastguard Worker     }
1173*9880d681SAndroid Build Coastguard Worker     assert(HandlerStack.empty());
1174*9880d681SAndroid Build Coastguard Worker   }
1175*9880d681SAndroid Build Coastguard Worker 
1176*9880d681SAndroid Build Coastguard Worker   // Now emit the clause info, starting with the number of clauses.
1177*9880d681SAndroid Build Coastguard Worker   OS.EmitIntValue(Clauses.size(), 4);
1178*9880d681SAndroid Build Coastguard Worker   for (ClrClause &Clause : Clauses) {
1179*9880d681SAndroid Build Coastguard Worker     // Emit a CORINFO_EH_CLAUSE :
1180*9880d681SAndroid Build Coastguard Worker     /*
1181*9880d681SAndroid Build Coastguard Worker       struct CORINFO_EH_CLAUSE
1182*9880d681SAndroid Build Coastguard Worker       {
1183*9880d681SAndroid Build Coastguard Worker           CORINFO_EH_CLAUSE_FLAGS Flags;         // actually a CorExceptionFlag
1184*9880d681SAndroid Build Coastguard Worker           DWORD                   TryOffset;
1185*9880d681SAndroid Build Coastguard Worker           DWORD                   TryLength;     // actually TryEndOffset
1186*9880d681SAndroid Build Coastguard Worker           DWORD                   HandlerOffset;
1187*9880d681SAndroid Build Coastguard Worker           DWORD                   HandlerLength; // actually HandlerEndOffset
1188*9880d681SAndroid Build Coastguard Worker           union
1189*9880d681SAndroid Build Coastguard Worker           {
1190*9880d681SAndroid Build Coastguard Worker               DWORD               ClassToken;   // use for catch clauses
1191*9880d681SAndroid Build Coastguard Worker               DWORD               FilterOffset; // use for filter clauses
1192*9880d681SAndroid Build Coastguard Worker           };
1193*9880d681SAndroid Build Coastguard Worker       };
1194*9880d681SAndroid Build Coastguard Worker 
1195*9880d681SAndroid Build Coastguard Worker       enum CORINFO_EH_CLAUSE_FLAGS
1196*9880d681SAndroid Build Coastguard Worker       {
1197*9880d681SAndroid Build Coastguard Worker           CORINFO_EH_CLAUSE_NONE    = 0,
1198*9880d681SAndroid Build Coastguard Worker           CORINFO_EH_CLAUSE_FILTER  = 0x0001, // This clause is for a filter
1199*9880d681SAndroid Build Coastguard Worker           CORINFO_EH_CLAUSE_FINALLY = 0x0002, // This clause is a finally clause
1200*9880d681SAndroid Build Coastguard Worker           CORINFO_EH_CLAUSE_FAULT   = 0x0004, // This clause is a fault clause
1201*9880d681SAndroid Build Coastguard Worker       };
1202*9880d681SAndroid Build Coastguard Worker       typedef enum CorExceptionFlag
1203*9880d681SAndroid Build Coastguard Worker       {
1204*9880d681SAndroid Build Coastguard Worker           COR_ILEXCEPTION_CLAUSE_NONE,
1205*9880d681SAndroid Build Coastguard Worker           COR_ILEXCEPTION_CLAUSE_FILTER  = 0x0001, // This is a filter clause
1206*9880d681SAndroid Build Coastguard Worker           COR_ILEXCEPTION_CLAUSE_FINALLY = 0x0002, // This is a finally clause
1207*9880d681SAndroid Build Coastguard Worker           COR_ILEXCEPTION_CLAUSE_FAULT = 0x0004,   // This is a fault clause
1208*9880d681SAndroid Build Coastguard Worker           COR_ILEXCEPTION_CLAUSE_DUPLICATED = 0x0008, // duplicated clause. This
1209*9880d681SAndroid Build Coastguard Worker                                                       // clause was duplicated
1210*9880d681SAndroid Build Coastguard Worker                                                       // to a funclet which was
1211*9880d681SAndroid Build Coastguard Worker                                                       // pulled out of line
1212*9880d681SAndroid Build Coastguard Worker       } CorExceptionFlag;
1213*9880d681SAndroid Build Coastguard Worker     */
1214*9880d681SAndroid Build Coastguard Worker     // Add 1 to the start/end of the EH clause; the IP associated with a
1215*9880d681SAndroid Build Coastguard Worker     // call when the runtime does its scan is the IP of the next instruction
1216*9880d681SAndroid Build Coastguard Worker     // (the one to which control will return after the call), so we need
1217*9880d681SAndroid Build Coastguard Worker     // to add 1 to the end of the clause to cover that offset.  We also add
1218*9880d681SAndroid Build Coastguard Worker     // 1 to the start of the clause to make sure that the ranges reported
1219*9880d681SAndroid Build Coastguard Worker     // for all clauses are disjoint.  Note that we'll need some additional
1220*9880d681SAndroid Build Coastguard Worker     // logic when machine traps are supported, since in that case the IP
1221*9880d681SAndroid Build Coastguard Worker     // that the runtime uses is the offset of the faulting instruction
1222*9880d681SAndroid Build Coastguard Worker     // itself; if such an instruction immediately follows a call but the
1223*9880d681SAndroid Build Coastguard Worker     // two belong to different clauses, we'll need to insert a nop between
1224*9880d681SAndroid Build Coastguard Worker     // them so the runtime can distinguish the point to which the call will
1225*9880d681SAndroid Build Coastguard Worker     // return from the point at which the fault occurs.
1226*9880d681SAndroid Build Coastguard Worker 
1227*9880d681SAndroid Build Coastguard Worker     const MCExpr *ClauseBegin =
1228*9880d681SAndroid Build Coastguard Worker         getOffsetPlusOne(Clause.StartLabel, FuncBeginSym);
1229*9880d681SAndroid Build Coastguard Worker     const MCExpr *ClauseEnd = getOffsetPlusOne(Clause.EndLabel, FuncBeginSym);
1230*9880d681SAndroid Build Coastguard Worker 
1231*9880d681SAndroid Build Coastguard Worker     const ClrEHUnwindMapEntry &Entry = FuncInfo.ClrEHUnwindMap[Clause.State];
1232*9880d681SAndroid Build Coastguard Worker     MachineBasicBlock *HandlerBlock = Entry.Handler.get<MachineBasicBlock *>();
1233*9880d681SAndroid Build Coastguard Worker     MCSymbol *BeginSym = getMCSymbolForMBB(Asm, HandlerBlock);
1234*9880d681SAndroid Build Coastguard Worker     const MCExpr *HandlerBegin = getOffset(BeginSym, FuncBeginSym);
1235*9880d681SAndroid Build Coastguard Worker     MCSymbol *EndSym = EndSymbolMap[Clause.State];
1236*9880d681SAndroid Build Coastguard Worker     const MCExpr *HandlerEnd = getOffset(EndSym, FuncBeginSym);
1237*9880d681SAndroid Build Coastguard Worker 
1238*9880d681SAndroid Build Coastguard Worker     uint32_t Flags = 0;
1239*9880d681SAndroid Build Coastguard Worker     switch (Entry.HandlerType) {
1240*9880d681SAndroid Build Coastguard Worker     case ClrHandlerType::Catch:
1241*9880d681SAndroid Build Coastguard Worker       // Leaving bits 0-2 clear indicates catch.
1242*9880d681SAndroid Build Coastguard Worker       break;
1243*9880d681SAndroid Build Coastguard Worker     case ClrHandlerType::Filter:
1244*9880d681SAndroid Build Coastguard Worker       Flags |= 1;
1245*9880d681SAndroid Build Coastguard Worker       break;
1246*9880d681SAndroid Build Coastguard Worker     case ClrHandlerType::Finally:
1247*9880d681SAndroid Build Coastguard Worker       Flags |= 2;
1248*9880d681SAndroid Build Coastguard Worker       break;
1249*9880d681SAndroid Build Coastguard Worker     case ClrHandlerType::Fault:
1250*9880d681SAndroid Build Coastguard Worker       Flags |= 4;
1251*9880d681SAndroid Build Coastguard Worker       break;
1252*9880d681SAndroid Build Coastguard Worker     }
1253*9880d681SAndroid Build Coastguard Worker     if (Clause.EnclosingState != MinClauseMap[Clause.State]) {
1254*9880d681SAndroid Build Coastguard Worker       // This is a "duplicate" clause; the handler needs to be entered from a
1255*9880d681SAndroid Build Coastguard Worker       // frame above the one holding the invoke.
1256*9880d681SAndroid Build Coastguard Worker       assert(Clause.EnclosingState > MinClauseMap[Clause.State]);
1257*9880d681SAndroid Build Coastguard Worker       Flags |= 8;
1258*9880d681SAndroid Build Coastguard Worker     }
1259*9880d681SAndroid Build Coastguard Worker     OS.EmitIntValue(Flags, 4);
1260*9880d681SAndroid Build Coastguard Worker 
1261*9880d681SAndroid Build Coastguard Worker     // Write the clause start/end
1262*9880d681SAndroid Build Coastguard Worker     OS.EmitValue(ClauseBegin, 4);
1263*9880d681SAndroid Build Coastguard Worker     OS.EmitValue(ClauseEnd, 4);
1264*9880d681SAndroid Build Coastguard Worker 
1265*9880d681SAndroid Build Coastguard Worker     // Write out the handler start/end
1266*9880d681SAndroid Build Coastguard Worker     OS.EmitValue(HandlerBegin, 4);
1267*9880d681SAndroid Build Coastguard Worker     OS.EmitValue(HandlerEnd, 4);
1268*9880d681SAndroid Build Coastguard Worker 
1269*9880d681SAndroid Build Coastguard Worker     // Write out the type token or filter offset
1270*9880d681SAndroid Build Coastguard Worker     assert(Entry.HandlerType != ClrHandlerType::Filter && "NYI: filters");
1271*9880d681SAndroid Build Coastguard Worker     OS.EmitIntValue(Entry.TypeToken, 4);
1272*9880d681SAndroid Build Coastguard Worker   }
1273*9880d681SAndroid Build Coastguard Worker }
1274