new testcase: instcombine should remove all the casts.

llvm-svn: 34869
This commit is contained in:
Chris Lattner 2007-03-03 05:24:06 +00:00
parent a0a23a645d
commit e1179e62fb

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@ -0,0 +1,24 @@
; Tests to make sure elimination of casts is working correctly
; RUN: llvm-as < %s | opt -instcombine -disable-output &&
; RUN: llvm-as < %s | opt -instcombine | llvm-dis | notcast
define i16 @test1(i16 %a) {
%tmp = zext i16 %a to i32 ; <i32> [#uses=2]
%tmp21 = lshr i32 %tmp, 8 ; <i32> [#uses=1]
%tmp5 = shl i32 %tmp, 8 ; <i32> [#uses=1]
%tmp.upgrd.32 = or i32 %tmp21, %tmp5 ; <i32> [#uses=1]
%tmp.upgrd.3 = trunc i32 %tmp.upgrd.32 to i16 ; <i16> [#uses=1]
ret i16 %tmp.upgrd.3
}
define i16 @test2(i16 %a) {
%tmp = zext i16 %a to i32 ; <i32> [#uses=2]
%tmp21 = lshr i32 %tmp, 9 ; <i32> [#uses=1]
%tmp5 = shl i32 %tmp, 8 ; <i32> [#uses=1]
%tmp.upgrd.32 = or i32 %tmp21, %tmp5 ; <i32> [#uses=1]
%tmp.upgrd.3 = trunc i32 %tmp.upgrd.32 to i16 ; <i16> [#uses=1]
ret i16 %tmp.upgrd.3
}