xref: /aosp_15_r20/external/llvm/test/CodeGen/X86/copy-eflags.ll (revision 9880d6810fe72a1726cb53787c6711e909410d58)
1*9880d681SAndroid Build Coastguard Worker; RUN: llc -o - %s | FileCheck %s
2*9880d681SAndroid Build Coastguard Worker; This tests for the problem originally reported in http://llvm.org/PR25951
3*9880d681SAndroid Build Coastguard Workertarget triple = "i686-unknown-linux-gnu"
4*9880d681SAndroid Build Coastguard Worker
5*9880d681SAndroid Build Coastguard Worker@b = common global i8 0, align 1
6*9880d681SAndroid Build Coastguard Worker@c = common global i32 0, align 4
7*9880d681SAndroid Build Coastguard Worker@a = common global i8 0, align 1
8*9880d681SAndroid Build Coastguard Worker@d = common global i8 0, align 1
9*9880d681SAndroid Build Coastguard Worker@.str = private unnamed_addr constant [4 x i8] c"%d\0A\00", align 1
10*9880d681SAndroid Build Coastguard Worker
11*9880d681SAndroid Build Coastguard Worker; CHECK-LABEL: func:
12*9880d681SAndroid Build Coastguard Worker; This tests whether eax is properly saved/restored around the lahf/sahf
13*9880d681SAndroid Build Coastguard Worker; instruction sequences.
14*9880d681SAndroid Build Coastguard Workerdefine i32 @func() {
15*9880d681SAndroid Build Coastguard Workerentry:
16*9880d681SAndroid Build Coastguard Worker  %bval = load i8, i8* @b
17*9880d681SAndroid Build Coastguard Worker  %inc = add i8 %bval, 1
18*9880d681SAndroid Build Coastguard Worker  store i8 %inc, i8* @b
19*9880d681SAndroid Build Coastguard Worker  %cval = load i32, i32* @c
20*9880d681SAndroid Build Coastguard Worker  %inc1 = add nsw i32 %cval, 1
21*9880d681SAndroid Build Coastguard Worker  store i32 %inc1, i32* @c
22*9880d681SAndroid Build Coastguard Worker  %aval = load i8, i8* @a
23*9880d681SAndroid Build Coastguard Worker  %inc2 = add i8 %aval, 1
24*9880d681SAndroid Build Coastguard Worker  store i8 %inc2, i8* @a
25*9880d681SAndroid Build Coastguard Worker; Copy flags produced by the incb of %inc1 to a register, need to save+restore
26*9880d681SAndroid Build Coastguard Worker; eax around it. The flags will be reused by %tobool.
27*9880d681SAndroid Build Coastguard Worker; CHECK: pushl %eax
28*9880d681SAndroid Build Coastguard Worker; CHECK: seto %al
29*9880d681SAndroid Build Coastguard Worker; CHECK: lahf
30*9880d681SAndroid Build Coastguard Worker; CHECK: movl %eax, [[REG:%[a-z]+]]
31*9880d681SAndroid Build Coastguard Worker; CHECK: popl %eax
32*9880d681SAndroid Build Coastguard Worker  %cmp = icmp eq i8 %aval, %bval
33*9880d681SAndroid Build Coastguard Worker  %conv5 = zext i1 %cmp to i8
34*9880d681SAndroid Build Coastguard Worker  store i8 %conv5, i8* @d
35*9880d681SAndroid Build Coastguard Worker  %tobool = icmp eq i32 %inc1, 0
36*9880d681SAndroid Build Coastguard Worker; We restore flags with an 'addb, sahf' sequence, need to save+restore eax
37*9880d681SAndroid Build Coastguard Worker; around it.
38*9880d681SAndroid Build Coastguard Worker; CHECK: pushl %eax
39*9880d681SAndroid Build Coastguard Worker; CHECK: movl [[REG]], %eax
40*9880d681SAndroid Build Coastguard Worker; CHECK: addb $127, %al
41*9880d681SAndroid Build Coastguard Worker; CHECK: sahf
42*9880d681SAndroid Build Coastguard Worker; CHECK: popl %eax
43*9880d681SAndroid Build Coastguard Worker  br i1 %tobool, label %if.end, label %if.then
44*9880d681SAndroid Build Coastguard Worker
45*9880d681SAndroid Build Coastguard Workerif.then:
46*9880d681SAndroid Build Coastguard Worker  %conv6 = sext i8 %inc to i32
47*9880d681SAndroid Build Coastguard Worker  %call = tail call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i32 0, i32 0), i32 %conv6)
48*9880d681SAndroid Build Coastguard Worker  br label %if.end
49*9880d681SAndroid Build Coastguard Worker
50*9880d681SAndroid Build Coastguard Workerif.end:
51*9880d681SAndroid Build Coastguard Worker  ret i32 0
52*9880d681SAndroid Build Coastguard Worker}
53*9880d681SAndroid Build Coastguard Worker
54*9880d681SAndroid Build Coastguard Workerdeclare i32 @printf(i8* nocapture readonly, ...)
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