Extended Description

cat case.c bisections
static int a, b = -2, c[1];
void foo(void);
int main() {
if ((c[0] &= (1 % b == 0)) > 1)
foo();
b = 1;
}

trunk can no longer eliminate foo:

clang-12 -v
clang version 12.0.1 (https://github.com/llvm/llvm-project.git fed4134)
Target: x86_64-unknown-linux-gnu

clang-12 case.c -S -O3 -o /dev/stdout
...

main: # @​main
.cfi_startproc

%bb.0:

movzbl	b(%rip), %eax
andl	%eax, c.0(%rip)
movb	$1, b(%rip)
xorl	%eax, %eax
retq

clang-trunk -v
clang version 14.0.0 (https://github.com/llvm/llvm-project.git 73346f5)
Target: x86_64-unknown-linux-gnu

clang-trunk case.c -S -O3 -o /dev/stdout
...
main: # @​main
.cfi_startproc

%bb.0:

pushq	%rax
.cfi_def_cfa_offset 16
movzbl	b(%rip), %eax
andl	c.0(%rip), %eax
movl	%eax, c.0(%rip)
cmpl	$2, %eax
jb	.LBB0_2

%bb.1:

callq	foo

.LBB0_2:
movb $1, b(%rip)
xorl %eax, %eax
popq %rcx
.cfi_def_cfa_offset 8
retq

183bbad introduced this regression