Souper says:

; Function: fn1
%0:i32 = var 
%1:i32 = lshr 1:i32, %0
%2:i1 = slt %1, 0:i32
cand %2 0:i1

COMMAND: /home/regehr/souper/build/souper -stp-path=/usr/local/bin/stp reduce_140/foo.bc

LLVM says:

define void @fn1() #0 {
entry:
  %0 = load i32* @a, align 4, !tbaa !1
  %shr = lshr i32 1, %0
  store i32 %shr, i32* @c, align 4, !tbaa !1
  %cmp = icmp slt i32 %shr, 0
  br i1 %cmp, label %lor.end, label %lor.rhs

lor.rhs:                                          ; preds = %entry
  store i32 0, i32* @b, align 4, !tbaa !1
  br label %lor.end

lor.end:                                          ; preds = %lor.rhs, %entry
  ret void
}

COMMAND: /home/regehr/souper/third_party/llvm/Debug/bin/clang -c -w -emit-llvm -O3 reduce_140/foo.c -o reduce_140/foo.bc

C source code:

int a, b, c;
void fn1() {
  c = 1 >> a;
  0 > c || (b = 0);
}

x86-64 from LLVM:

fn1:                                    # @fn1
	movb	a(%rip), %cl
	movl	$1, %eax
	shrl	%cl, %eax
	testl	%eax, %eax
	movl	%eax, c(%rip)
	js	.LBB0_2
	movl	$0, b(%rip)
.LBB0_2:                                # %lor.end
	retq

COMMAND: /home/regehr/souper/third_party/llvm/Debug/bin/clang -w -O3 reduce_140/foo.c -S -o -

x86-64 from GCC:

fn1:
	movl	a(%rip), %ecx
	movl	$1, %eax
	sarl	%cl, %eax
	testl	%eax, %eax
	movl	%eax, c(%rip)
	js	.L1
	movl	$0, b(%rip)
.L1:
	rep ret

COMMAND: gcc -w -O3 reduce_140/foo.c -S -o -