[llvm] 7a55989 - [InstCombine] Add some basic trunc(lshr(zext(x), c)) tests

[Simon Pilgrim via llvm-commits]

Author: Simon Pilgrim
Date: 2020-09-29T15:49:57+01:00
New Revision: 7a55989dc4305e66734bdd84a9f9eefeb9fe64bd

URL: https://github.com/llvm/llvm-project/commit/7a55989dc4305e66734bdd84a9f9eefeb9fe64bd
DIFF: https://github.com/llvm/llvm-project/commit/7a55989dc4305e66734bdd84a9f9eefeb9fe64bd.diff

LOG: [InstCombine] Add some basic trunc(lshr(zext(x),c)) tests

Copied from the sext equivalents

Added: 
    

Modified: 
    llvm/test/Transforms/InstCombine/cast.ll

Removed: 
    


################################################################################
diff  --git a/llvm/test/Transforms/InstCombine/cast.ll b/llvm/test/Transforms/InstCombine/cast.ll
index 97439606973c..c5f18b4c625e 100644
--- a/llvm/test/Transforms/InstCombine/cast.ll
+++ b/llvm/test/Transforms/InstCombine/cast.ll
@@ -2012,6 +2012,90 @@ define i8 @trunc_lshr_overshift2_sext_uses3(i8 %A) {
   ret i8 %D
 }
 
+define i8 @trunc_lshr_zext(i8 %A) {
+; ALL-LABEL: @trunc_lshr_zext(
+; ALL-NEXT:    [[TMP1:%.*]] = lshr i8 [[A:%.*]], 6
+; ALL-NEXT:    ret i8 [[TMP1]]
+;
+  %B = zext i8 %A to i32
+  %C = lshr i32 %B, 6
+  %D = trunc i32 %C to i8
+  ret i8 %D
+}
+
+define i8 @trunc_lshr_zext_exact(i8 %A) {
+; ALL-LABEL: @trunc_lshr_zext_exact(
+; ALL-NEXT:    [[TMP1:%.*]] = lshr i8 [[A:%.*]], 6
+; ALL-NEXT:    ret i8 [[TMP1]]
+;
+  %B = zext i8 %A to i32
+  %C = lshr exact i32 %B, 6
+  %D = trunc i32 %C to i8
+  ret i8 %D
+}
+
+define <2 x i8> @trunc_lshr_zext_uniform(<2 x i8> %A) {
+; ALL-LABEL: @trunc_lshr_zext_uniform(
+; ALL-NEXT:    [[TMP1:%.*]] = lshr <2 x i8> [[A:%.*]], <i8 6, i8 6>
+; ALL-NEXT:    ret <2 x i8> [[TMP1]]
+;
+  %B = zext <2 x i8> %A to <2 x i32>
+  %C = lshr <2 x i32> %B, <i32 6, i32 6>
+  %D = trunc <2 x i32> %C to <2 x i8>
+  ret <2 x i8> %D
+}
+
+define <2 x i8> @trunc_lshr_zext_uniform_undef(<2 x i8> %A) {
+; ALL-LABEL: @trunc_lshr_zext_uniform_undef(
+; ALL-NEXT:    [[B:%.*]] = zext <2 x i8> [[A:%.*]] to <2 x i32>
+; ALL-NEXT:    [[C:%.*]] = lshr <2 x i32> [[B]], <i32 6, i32 undef>
+; ALL-NEXT:    [[D:%.*]] = trunc <2 x i32> [[C]] to <2 x i8>
+; ALL-NEXT:    ret <2 x i8> [[D]]
+;
+  %B = zext <2 x i8> %A to <2 x i32>
+  %C = lshr <2 x i32> %B, <i32 6, i32 undef>
+  %D = trunc <2 x i32> %C to <2 x i8>
+  ret <2 x i8> %D
+}
+
+define <2 x i8> @trunc_lshr_zext_nonuniform(<2 x i8> %A) {
+; ALL-LABEL: @trunc_lshr_zext_nonuniform(
+; ALL-NEXT:    [[C:%.*]] = lshr <2 x i8> [[A:%.*]], <i8 6, i8 2>
+; ALL-NEXT:    ret <2 x i8> [[C]]
+;
+  %B = zext <2 x i8> %A to <2 x i32>
+  %C = lshr <2 x i32> %B, <i32 6, i32 2>
+  %D = trunc <2 x i32> %C to <2 x i8>
+  ret <2 x i8> %D
+}
+
+define <3 x i8> @trunc_lshr_zext_nonuniform_undef(<3 x i8> %A) {
+; ALL-LABEL: @trunc_lshr_zext_nonuniform_undef(
+; ALL-NEXT:    [[B:%.*]] = zext <3 x i8> [[A:%.*]] to <3 x i32>
+; ALL-NEXT:    [[C:%.*]] = lshr <3 x i32> [[B]], <i32 6, i32 2, i32 undef>
+; ALL-NEXT:    [[D:%.*]] = trunc <3 x i32> [[C]] to <3 x i8>
+; ALL-NEXT:    ret <3 x i8> [[D]]
+;
+  %B = zext <3 x i8> %A to <3 x i32>
+  %C = lshr <3 x i32> %B, <i32 6, i32 2, i32 undef>
+  %D = trunc <3 x i32> %C to <3 x i8>
+  ret <3 x i8> %D
+}
+
+define <2 x i8> @trunc_lshr_zext_uses1(<2 x i8> %A) {
+; ALL-LABEL: @trunc_lshr_zext_uses1(
+; ALL-NEXT:    [[B:%.*]] = zext <2 x i8> [[A:%.*]] to <2 x i32>
+; ALL-NEXT:    call void @use_v2i32(<2 x i32> [[B]])
+; ALL-NEXT:    [[C:%.*]] = lshr <2 x i8> [[A]], <i8 6, i8 6>
+; ALL-NEXT:    ret <2 x i8> [[C]]
+;
+  %B = zext <2 x i8> %A to <2 x i32>
+  call void @use_v2i32(<2 x i32> %B)
+  %C = lshr <2 x i32> %B, <i32 6, i32 6>
+  %D = trunc <2 x i32> %C to <2 x i8>
+  ret <2 x i8> %D
+}
+
 ; The following four tests sext + lshr + trunc patterns.
 ; PR33078