llvm-6502/test/Transforms/InstCombine/bit-tracking.ll
Tanya Lattner 76806b6a43 Remove llvm-upgrade and update tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48103 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-09 08:16:40 +00:00

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
}