maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity

[InstCombine] add tests to show missing trunc optimizations 

llvm-svn: 253609
This commit is contained in:
Sanjay Patel 2015-11-19 22:11:52 +00:00
parent 145e4d6471
commit c4aa50414b
1 changed files with 46 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

46
llvm/test/Transforms/InstCombine/trunc.ll
View File

@ -118,3 +118,49 @@ define i8 @test10(i32 %X) {
; CHECK: and
; CHECK: ret
}
; PR25543
; https://llvm.org/bugs/show_bug.cgi?id=25543
; TODO: This could be extractelement.
define i32 @trunc_bitcast1(<4 x i32> %v) {
%bc = bitcast <4 x i32> %v to i128
%shr = lshr i128 %bc, 32
%ext = trunc i128 %shr to i32
ret i32 %ext
; CHECK-LABEL: @trunc_bitcast1(
; CHECK-NEXT: %bc = bitcast <4 x i32> %v to i128
; CHECK-NEXT: %shr = lshr i128 %bc, 32
; CHECK-NEXT: %ext = trunc i128 %shr to i32
; CHECK-NEXT: ret i32 %ext
}
; TODO: This could be bitcast + extractelement.
define i32 @trunc_bitcast2(<2 x i64> %v) {
%bc = bitcast <2 x i64> %v to i128
%shr = lshr i128 %bc, 64
%ext = trunc i128 %shr to i32
ret i32 %ext
; CHECK-LABEL: @trunc_bitcast2(
; CHECK-NEXT: %bc = bitcast <2 x i64> %v to i128
; CHECK-NEXT: %shr = lshr i128 %bc, 64
; CHECK-NEXT: %ext = trunc i128 %shr to i32
; CHECK-NEXT: ret i32 %ext
}
; TODO: The shift is optional. This could be extractelement.
define i32 @trunc_bitcast3(<4 x i32> %v) {
%bc = bitcast <4 x i32> %v to i128
%ext = trunc i128 %bc to i32
ret i32 %ext
; CHECK-LABEL: @trunc_bitcast3(
; CHECK-NEXT: %bc = bitcast <4 x i32> %v to i128
; CHECK-NEXT: %ext = trunc i128 %bc to i32
; CHECK-NEXT: ret i32 %ext
}