mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2024-11-02 00:42:52 +01:00
27 lines
1.1 KiB
LLVM
27 lines
1.1 KiB
LLVM
; This file contains various testcases that require tracking whether bits are
|
|
; set or cleared by various instructions.
|
|
; RUN: llvm-as < %s | opt -instcombine -instcombine | llvm-dis |\
|
|
; RUN: not grep %ELIM
|
|
|
|
; Reduce down to a single XOR
|
|
define i32 @test3(i32 %B) {
|
|
%ELIMinc = and i32 %B, 1 ; <i32> [#uses=1]
|
|
%tmp.5 = xor i32 %ELIMinc, 1 ; <i32> [#uses=1]
|
|
%ELIM7 = and i32 %B, -2 ; <i32> [#uses=1]
|
|
%tmp.8 = or i32 %tmp.5, %ELIM7 ; <i32> [#uses=1]
|
|
ret i32 %tmp.8
|
|
}
|
|
|
|
; Finally, a bigger case where we chain things together. This corresponds to
|
|
; incrementing a single-bit bitfield, which should become just an xor.
|
|
define i32 @test4(i32 %B) {
|
|
%ELIM3 = shl i32 %B, 31 ; <i32> [#uses=1]
|
|
%ELIM4 = ashr i32 %ELIM3, 31 ; <i32> [#uses=1]
|
|
%inc = add i32 %ELIM4, 1 ; <i32> [#uses=1]
|
|
%ELIM5 = and i32 %inc, 1 ; <i32> [#uses=1]
|
|
%ELIM7 = and i32 %B, -2 ; <i32> [#uses=1]
|
|
%tmp.8 = or i32 %ELIM5, %ELIM7 ; <i32> [#uses=1]
|
|
ret i32 %tmp.8
|
|
}
|
|
|