[DAGCombiner] visitRotate patch to optimize pair of ROTR/ROTL instructions into one with combined shift operand.
For two ROTR operations with shifts C1, C2; combined shift operand will be (C1 + C2) % bitsize.
Differential revision: https://reviews.llvm.org/D12833
llvm-svn: 307179
diff --git a/llvm/test/CodeGen/ARM/ror.ll b/llvm/test/CodeGen/ARM/ror.ll
index a6cc415..0f699a8 100644
--- a/llvm/test/CodeGen/ARM/ror.ll
+++ b/llvm/test/CodeGen/ARM/ror.ll
@@ -3,8 +3,7 @@
; rotr (rotr x, 4), 6 -> rotr x, 10 -> ror r0, r0, #10
define i32 @test1(i32 %x) nounwind readnone {
; CHECK-LABEL: test1:
-; CHECK: ror r0, r0, #4
-; CHECK: ror r0, r0, #6
+; CHECK: ror r0, r0, #10
; CHECK: bx lr
entry:
%high_part.i = shl i32 %x, 28
@@ -19,10 +18,8 @@
; the same vector test
define <2 x i32> @test2(<2 x i32> %x) nounwind readnone {
; CHECK-LABEL: test2:
-; CHECK: ror r0, r0, #4
-; CHECK: ror r1, r1, #4
-; CHECK: ror r0, r0, #6
-; CHECK: ror r1, r1, #6
+; CHECK: ror r0, r0, #10
+; CHECK: ror r1, r1, #10
; CHECK: bx lr
entry:
%high_part.i = shl <2 x i32> %x, <i32 28, i32 28>
diff --git a/llvm/test/CodeGen/X86/combine-rotates.ll b/llvm/test/CodeGen/X86/combine-rotates.ll
index 46a8b68..1bce1cf 100644
--- a/llvm/test/CodeGen/X86/combine-rotates.ll
+++ b/llvm/test/CodeGen/X86/combine-rotates.ll
@@ -35,8 +35,7 @@
define <4 x i32> @combine_vec_rot_rot_splat(<4 x i32> %x) {
; XOP-LABEL: combine_vec_rot_rot_splat:
; XOP: # BB#0:
-; XOP-NEXT: vprotd $29, %xmm0, %xmm0
-; XOP-NEXT: vprotd $10, %xmm0, %xmm0
+; XOP-NEXT: vprotd $7, %xmm0, %xmm0
; XOP-NEXT: retq
;
; AVX512-LABEL: combine_vec_rot_rot_splat:
@@ -60,8 +59,7 @@
define <4 x i32> @combine_vec_rot_rot_splat_zero(<4 x i32> %x) {
; XOP-LABEL: combine_vec_rot_rot_splat_zero:
; XOP: # BB#0:
-; XOP-NEXT: vprotd $31, %xmm0, %xmm0
-; XOP-NEXT: vprotd $1, %xmm0, %xmm0
+; XOP-NEXT: vprotd $0, %xmm0, %xmm0
; XOP-NEXT: retq
;
; AVX512-LABEL: combine_vec_rot_rot_splat_zero: