Souper says:
; Function: fn1
%0:i32 = var
%1:i1 = slt 0:i32, %0
%2:i32 = var
%3:i1 = slt 0:i32, %2
%4:i32 = zext %3
%5:i1 = slt %0, %4
%6:i1 = and %1, %5
cand %6 0:i1
COMMAND: /home/regehr/souper/build/souper -stp-path=/usr/local/bin/stp reduce_780/foo.bc
LLVM says:
define void @fn1() #0 {
entry:
%0 = load i32* @b, align 4, !tbaa !1
%cmp = icmp sgt i32 %0, 0
%conv = zext i1 %cmp to i32
store i32 %conv, i32* @d, align 4, !tbaa !1
%1 = load i32* @a, align 4, !tbaa !1
%cmp1 = icmp sgt i32 %1, 0
%cmp3 = icmp sgt i32 %conv, %1
%cmp3. = and i1 %cmp1, %cmp3
%land.ext = zext i1 %cmp3. to i32
store i32 %land.ext, i32* @c, align 4, !tbaa !1
ret void
}
COMMAND: /home/regehr/souper/third_party/llvm/Debug/bin/clang -c -w -emit-llvm -O3 reduce_780/foo.c -o reduce_780/foo.bc
C source code:
int a, b, c, d;
void fn1() {
d = 0 < b;
c = a > 0 && d > a;
}
x86-64 from LLVM:
fn1: # @fn1
cmpl $0, b(%rip)
setg %al
movzbl %al, %eax
movl %eax, d(%rip)
movl a(%rip), %ecx
testl %ecx, %ecx
setg %dl
cmpl %ecx, %eax
setg %al
andb %dl, %al
movzbl %al, %eax
movl %eax, c(%rip)
retq
COMMAND: /home/regehr/souper/third_party/llvm/Debug/bin/clang -w -O3 reduce_780/foo.c -S -o -
x86-64 from GCC:
fn1:
movl b(%rip), %edx
xorl %eax, %eax
movl $0, c(%rip)
testl %edx, %edx
setg %al
movl %eax, d(%rip)
ret
COMMAND: gcc -w -O3 reduce_780/foo.c -S -o -