Souper says:
; Function: fn2
%0:i32 = var
%1:i1 = eq 0:i32, %0
%2:i32 = var
%3:i1 = eq 0:i32, %2
%4:i32 = zext %3
%5:i32 = xor %0, %4
%6:i1 = eq 8:i32, %5
%7:i1 = and %1, %6
cand %7 0:i1
COMMAND: /home/regehr/souper/build/souper -stp-path=/usr/local/bin/stp reduce_1/foo.bc
LLVM says:
define i32 @fn1(i32 %p1, i32 %p2) #0 {
entry:
%cmp = icmp eq i32 %p1, 8
%cmp1 = icmp eq i32 %p2, 0
%cmp1. = and i1 %cmp, %cmp1
%land.ext = zext i1 %cmp1. to i32
ret i32 %land.ext
}
define void @fn2() #1 {
entry:
%0 = load i32* @a, align 4, !tbaa !1
%cmp = icmp eq i32 %0, 0
%conv = zext i1 %cmp to i32
store i32 %conv, i32* @c, align 4, !tbaa !1
%1 = load i32* @b, align 4, !tbaa !1
%xor = xor i32 %conv, %1
%cmp.i = icmp eq i32 %xor, 8
%cmp1.i = icmp eq i32 %1, 0
%cmp1..i = and i1 %cmp.i, %cmp1.i
%land.ext.i = zext i1 %cmp1..i to i32
store i32 %land.ext.i, i32* @d, align 4, !tbaa !1
ret void
}
COMMAND: /home/regehr/souper/third_party/llvm/Debug/bin/clang -c -w -emit-llvm -O3 reduce_1/foo.c -o reduce_1/foo.bc
C source code:
int a, b, c, d;
int fn1(p1, p2) { return p1 == 8 && p2 == 0; }
void fn2() {
c = a == 0;
d = fn1(c ^ b, b);
}
x86-64 from LLVM:
fn1: # @fn1
cmpl $8, %edi
sete %al
testl %esi, %esi
sete %cl
andb %al, %cl
movzbl %cl, %eax
retq
fn2: # @fn2
cmpl $0, a(%rip)
sete %al
movzbl %al, %eax
movl %eax, c(%rip)
movl b(%rip), %ecx
xorl %ecx, %eax
cmpl $8, %eax
sete %al
testl %ecx, %ecx
sete %cl
andb %al, %cl
movzbl %cl, %eax
movl %eax, d(%rip)
retq
.Ltmp1:
COMMAND: /home/regehr/souper/third_party/llvm/Debug/bin/clang -w -O3 reduce_1/foo.c -S -o -
x86-64 from GCC:
fn1:
cmpl $8, %edi
sete %dl
xorl %eax, %eax
testl %esi, %esi
sete %al
andl %edx, %eax
ret
fn2:
.LFB1:
movl a(%rip), %eax
xorl %edx, %edx
testl %eax, %eax
movl b(%rip), %eax
sete %dl
movl %edx, c(%rip)
xorl %eax, %edx
cmpl $8, %edx
sete %dl
testl %eax, %eax
sete %al
movzbl %al, %eax
andl %edx, %eax
movl %eax, d(%rip)
ret
.LFE1:
COMMAND: gcc -w -O3 reduce_1/foo.c -S -o -