Souper says:
; Function: fn1
%0:i32 = var
%1:i64 = sext %0
%2:i64 = sdiv 21474836471:i64, %1
%3:i1 = ne 0:i64, %2
cand %3 1:i1
COMMAND: /home/regehr/souper/build/souper -stp-path=/usr/local/bin/stp reduce_296/foo.bc
LLVM says:
define i32 @fn1() #0 {
entry:
%0 = load i32* @a, align 4, !tbaa !1
%conv = sext i32 %0 to i64
%div = sdiv i64 21474836471, %conv
%tobool = icmp ne i64 %div, 0
%lor.ext = zext i1 %tobool to i32
ret i32 %lor.ext
}
COMMAND: /home/regehr/souper/third_party/llvm/Debug/bin/clang -c -w -emit-llvm -O3 reduce_296/foo.c -o reduce_296/foo.bc
C source code:
int a;
int fn1() { return 21474836471 / a || 0; }
x86-64 from LLVM:
fn1: # @fn1
movslq a(%rip), %rcx
movabsq $21474836471, %rax # imm = 0x4FFFFFFF7
xorl %edx, %edx
idivq %rcx
testq %rax, %rax
setne %al
movzbl %al, %eax
retq
COMMAND: /home/regehr/souper/third_party/llvm/Debug/bin/clang -w -O3 reduce_296/foo.c -S -o -
x86-64 from GCC:
fn1:
movslq a(%rip), %rcx
movabsq $21474836471, %rax
cqto
idivq %rcx
testq %rax, %rax
setne %al
movzbl %al, %eax
ret
COMMAND: gcc -w -O3 reduce_296/foo.c -S -o -