1*638691a0SAndroid Build Coastguard Worker# MMX assist routines for peakval 2*638691a0SAndroid Build Coastguard Worker# Copyright 2001 Phil Karn, KA9Q 3*638691a0SAndroid Build Coastguard Worker# May be used under the terms of the GNU Lesser General Public License (LGPL) 4*638691a0SAndroid Build Coastguard Worker 5*638691a0SAndroid Build Coastguard Worker .text 6*638691a0SAndroid Build Coastguard Worker 7*638691a0SAndroid Build Coastguard Worker# Find peak value in signed 16-bit input samples 8*638691a0SAndroid Build Coastguard Worker# int peakval_mmx_assist(signed short *in,int cnt); 9*638691a0SAndroid Build Coastguard Worker .global peakval_mmx_assist 10*638691a0SAndroid Build Coastguard Worker .type peakval_mmx_assist,@function 11*638691a0SAndroid Build Coastguard Worker .align 16 12*638691a0SAndroid Build Coastguard Workerpeakval_mmx_assist: 13*638691a0SAndroid Build Coastguard Worker pushl %ebp 14*638691a0SAndroid Build Coastguard Worker movl %esp,%ebp 15*638691a0SAndroid Build Coastguard Worker pushl %esi 16*638691a0SAndroid Build Coastguard Worker pushl %ecx 17*638691a0SAndroid Build Coastguard Worker pushl %ebx 18*638691a0SAndroid Build Coastguard Worker 19*638691a0SAndroid Build Coastguard Worker movl 8(%ebp),%esi 20*638691a0SAndroid Build Coastguard Worker movl 12(%ebp),%ecx 21*638691a0SAndroid Build Coastguard Worker 22*638691a0SAndroid Build Coastguard Worker pxor %mm7,%mm7 # clear peak 23*638691a0SAndroid Build Coastguard Worker 24*638691a0SAndroid Build Coastguard Worker1: subl $4,%ecx 25*638691a0SAndroid Build Coastguard Worker jl 2f 26*638691a0SAndroid Build Coastguard Worker movq (%esi),%mm0 27*638691a0SAndroid Build Coastguard Worker movq %mm0,%mm1 28*638691a0SAndroid Build Coastguard Worker psraw $15,%mm1 # mm1 = 1's if negative, 0's if positive 29*638691a0SAndroid Build Coastguard Worker pxor %mm1,%mm0 # complement negatives 30*638691a0SAndroid Build Coastguard Worker psubw %mm1,%mm0 # add 1 to negatives 31*638691a0SAndroid Build Coastguard Worker movq %mm7,%mm6 # copy previous peak 32*638691a0SAndroid Build Coastguard Worker pcmpgtw %mm0,%mm6 # ff == old peak greater 33*638691a0SAndroid Build Coastguard Worker pand %mm6,%mm7 # select old peaks that are greater 34*638691a0SAndroid Build Coastguard Worker pandn %mm0,%mm6 # select new values that are greater 35*638691a0SAndroid Build Coastguard Worker por %mm6,%mm7 36*638691a0SAndroid Build Coastguard Worker 37*638691a0SAndroid Build Coastguard Worker addl $8,%esi 38*638691a0SAndroid Build Coastguard Worker jmp 1b 39*638691a0SAndroid Build Coastguard Worker 40*638691a0SAndroid Build Coastguard Worker2: movd %mm7,%eax 41*638691a0SAndroid Build Coastguard Worker psrlq $16,%mm7 42*638691a0SAndroid Build Coastguard Worker andl $0xffff,%eax 43*638691a0SAndroid Build Coastguard Worker 44*638691a0SAndroid Build Coastguard Worker movd %mm7,%edx 45*638691a0SAndroid Build Coastguard Worker psrlq $16,%mm7 46*638691a0SAndroid Build Coastguard Worker andl $0xffff,%edx 47*638691a0SAndroid Build Coastguard Worker cmpl %edx,%eax 48*638691a0SAndroid Build Coastguard Worker jnl 3f 49*638691a0SAndroid Build Coastguard Worker movl %edx,%eax 50*638691a0SAndroid Build Coastguard Worker3: 51*638691a0SAndroid Build Coastguard Worker movd %mm7,%edx 52*638691a0SAndroid Build Coastguard Worker psrlq $16,%mm7 53*638691a0SAndroid Build Coastguard Worker andl $0xffff,%edx 54*638691a0SAndroid Build Coastguard Worker cmpl %edx,%eax 55*638691a0SAndroid Build Coastguard Worker jnl 4f 56*638691a0SAndroid Build Coastguard Worker movl %edx,%eax 57*638691a0SAndroid Build Coastguard Worker4: 58*638691a0SAndroid Build Coastguard Worker movd %mm7,%edx 59*638691a0SAndroid Build Coastguard Worker andl $0xffff,%edx 60*638691a0SAndroid Build Coastguard Worker cmpl %edx,%eax 61*638691a0SAndroid Build Coastguard Worker jnl 5f 62*638691a0SAndroid Build Coastguard Worker movl %edx,%eax 63*638691a0SAndroid Build Coastguard Worker5: 64*638691a0SAndroid Build Coastguard Worker emms 65*638691a0SAndroid Build Coastguard Worker popl %ebx 66*638691a0SAndroid Build Coastguard Worker popl %ecx 67*638691a0SAndroid Build Coastguard Worker popl %esi 68*638691a0SAndroid Build Coastguard Worker popl %ebp 69*638691a0SAndroid Build Coastguard Worker ret 70*638691a0SAndroid Build Coastguard Worker 71