[llvm] b85de2c - [InstCombine] Add bswap(trunc(bswap(x))) -> trunc(lshr(x, c)) vector tests

[Simon Pilgrim via llvm-commits]

Author: Simon Pilgrim
Date: 2020-09-30T16:01:08+01:00
New Revision: b85de2c69cf3d6fbc2ad3439a6224667a58f704c

URL: https://github.com/llvm/llvm-project/commit/b85de2c69cf3d6fbc2ad3439a6224667a58f704c
DIFF: https://github.com/llvm/llvm-project/commit/b85de2c69cf3d6fbc2ad3439a6224667a58f704c.diff

LOG: [InstCombine] Add bswap(trunc(bswap(x))) -> trunc(lshr(x, c)) vector tests

Add tests showing failure to correctly fold vector bswap(trunc(bswap(x))) intrinsic patterns

Added: 
    

Modified: 
    llvm/test/Transforms/InstCombine/bswap-fold.ll

Removed: 
    


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diff  --git a/llvm/test/Transforms/InstCombine/bswap-fold.ll b/llvm/test/Transforms/InstCombine/bswap-fold.ll
index 5e9c0923d6c5..c90b880f0ea7 100644
--- a/llvm/test/Transforms/InstCombine/bswap-fold.ll
+++ b/llvm/test/Transforms/InstCombine/bswap-fold.ll
@@ -37,6 +37,16 @@ define i16 @test7(i32 %A) {
   ret i16 %D
 }
 
+define <2 x i16> @test7_vector(<2 x i32> %A) {
+; CHECK-LABEL: @test7_vector(
+; CHECK-NEXT:    ret <2 x i16> undef
+;
+  %B = tail call <2 x i32> @llvm.bswap.v2i32(<2 x i32> %A) nounwind
+  %C = trunc <2 x i32> %B to <2 x i16>
+  %D = tail call <2 x i16> @llvm.bswap.v2i16(<2 x i16> %C) nounwind
+  ret <2 x i16> %D
+}
+
 define i16 @test8(i64 %A) {
 ; CHECK-LABEL: @test8(
 ; CHECK-NEXT:    [[TMP1:%.*]] = lshr i64 [[A:%.*]], 48
@@ -49,6 +59,16 @@ define i16 @test8(i64 %A) {
   ret i16 %D
 }
 
+define <2 x i16> @test8_vector(<2 x i64> %A) {
+; CHECK-LABEL: @test8_vector(
+; CHECK-NEXT:    ret <2 x i16> undef
+;
+  %B = tail call <2 x i64> @llvm.bswap.v2i64(<2 x i64> %A) nounwind
+  %C = trunc <2 x i64> %B to <2 x i16>
+  %D = tail call <2 x i16> @llvm.bswap.v2i16(<2 x i16> %C) nounwind
+  ret <2 x i16> %D
+}
+
 ; Misc: Fold bswap(undef) to undef.
 define i64 @foo() {
 ; CHECK-LABEL: @foo(
@@ -334,4 +354,6 @@ define i64 @bs_and64i_multiuse(i64 %a, i64 %b) #0 {
 declare i16 @llvm.bswap.i16(i16)
 declare i32 @llvm.bswap.i32(i32)
 declare i64 @llvm.bswap.i64(i64)
+declare <2 x i16> @llvm.bswap.v2i16(<2 x i16>)
 declare <2 x i32> @llvm.bswap.v2i32(<2 x i32>)
+declare <2 x i64> @llvm.bswap.v2i64(<2 x i64>)