llvm/test/CodeGen/X86/and-encoding.ll
Elena Demikhovsky 558bab1214 Optimized loading (zextload) of i1 value from memory.
This patch is a partial revert of https://llvm.org/svn/llvm-project/llvm/trunk@237793.
Extra "and" causes performance degradation.

We assume that i1 is stored in zero-extended form. And store operation is responsible for zeroing upper bits.

Differential Revision: http://reviews.llvm.org/D17541



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@261828 91177308-0d34-0410-b5e6-96231b3b80d8
2016-02-25 07:05:12 +00:00

33 lines
790 B
LLVM

; RUN: llc -show-mc-encoding < %s | FileCheck %s
; Test that the direct object emission selects the and variant with 8 bit
; immediate.
; We used to get this wrong when using direct object emission, but not when
; reading assembly.
target triple = "x86_64-pc-linux"
define void @f1() {
; CHECK-LABEL: f1:
; CHECK: andq $-32, %rsp # encoding: [0x48,0x83,0xe4,0xe0]
%foo = alloca i8, align 32
ret void
}
define void @f2(i16 %x, i1 *%y) {
; CHECK-LABEL: f2:
; CHECK: andl $1, %edi # encoding: [0x83,0xe7,0x01]
%c = trunc i16 %x to i1
store i1 %c, i1* %y
ret void
}
define void @f3(i32 %x, i1 *%y) {
; CHECK-LABEL: f3:
; CHECK: andl $1, %edi # encoding: [0x83,0xe7,0x01]
%c = trunc i32 %x to i1
store i1 %c, i1* %y
ret void
}