llvm-6502/test/CodeGen/X86/bit-test-shift.ll at 4e8f68f24593b70164f09fec837f4bca3fd8951d - llvm-6502 - Applefritter: Git

6502/llvm-6502

mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2025-11-04 05:17:07 +00:00

Files

Owen Anderson ed1088afb5 A select between a constant and zero, when fed by a bit test, can be efficiently

lowered using a series of shifts.
Fixes <rdar://problem/8285015>.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114599 91177308-0d34-0410-b5e6-96231b3b80d8

2010-09-22 22:58:22 +00:00

14 lines

323 B

LLVM

Raw Blame History

 ; RUN: llc < %s -march=x86 | FileCheck %s
 ; <rdar://problem/8285015>
 define i32 @x(i32 %t) nounwind readnone ssp {
 entry:
 ; CHECK: shll	$23, %eax
 ; CHECK: sarl	$31, %eax
 ; CHECK: andl	$-26, %eax
   %and = and i32 %t, 256
   %tobool = icmp eq i32 %and, 0
   %retval.0 = select i1 %tobool, i32 0, i32 -26
   ret i32 %retval.0
 }