[llvm] r346504 - [SystemZ] Avoid inserting same value after replication
Jonas Paulsson via llvm-commits
llvm-commits at lists.llvm.org
Fri Nov 9 07:44:28 PST 2018
Author: jonpa
Date: Fri Nov 9 07:44:28 2018
New Revision: 346504
URL: http://llvm.org/viewvc/llvm-project?rev=346504&view=rev
Log:
[SystemZ] Avoid inserting same value after replication
A minor improvement of buildVector() that skips creating an
INSERT_VECTOR_ELT for a Value which has already been used for the
REPLICATE.
Review: Ulrich Weigand
https://reviews.llvm.org/D54315
Added:
llvm/trunk/test/CodeGen/SystemZ/vec-move-19.ll
Modified:
llvm/trunk/lib/Target/SystemZ/SystemZISelLowering.cpp
Modified: llvm/trunk/lib/Target/SystemZ/SystemZISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/SystemZ/SystemZISelLowering.cpp?rev=346504&r1=346503&r2=346504&view=diff
==============================================================================
--- llvm/trunk/lib/Target/SystemZ/SystemZISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/SystemZ/SystemZISelLowering.cpp Fri Nov 9 07:44:28 2018
@@ -4479,6 +4479,7 @@ static SDValue buildVector(SelectionDAG
// Constants with undefs to get a full vector constant and use that
// as the starting point.
SDValue Result;
+ SDValue ReplicatedVal;
if (NumConstants > 0) {
for (unsigned I = 0; I < NumElements; ++I)
if (!Constants[I].getNode())
@@ -4500,6 +4501,7 @@ static SDValue buildVector(SelectionDAG
if (LoadElIdx != UINT_MAX) {
Result = DAG.getNode(SystemZISD::REPLICATE, DL, VT, Elems[LoadElIdx]);
Done[LoadElIdx] = true;
+ ReplicatedVal = Elems[LoadElIdx];
} else {
// Try to use VLVGP.
unsigned I1 = NumElements / 2 - 1;
@@ -4520,7 +4522,7 @@ static SDValue buildVector(SelectionDAG
// Use VLVGx to insert the other elements.
for (unsigned I = 0; I < NumElements; ++I)
- if (!Done[I] && !Elems[I].isUndef())
+ if (!Done[I] && !Elems[I].isUndef() && Elems[I] != ReplicatedVal)
Result = DAG.getNode(ISD::INSERT_VECTOR_ELT, DL, VT, Result, Elems[I],
DAG.getConstant(I, DL, MVT::i32));
return Result;
Added: llvm/trunk/test/CodeGen/SystemZ/vec-move-19.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/SystemZ/vec-move-19.ll?rev=346504&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/SystemZ/vec-move-19.ll (added)
+++ llvm/trunk/test/CodeGen/SystemZ/vec-move-19.ll Fri Nov 9 07:44:28 2018
@@ -0,0 +1,20 @@
+; RUN: llc < %s -mtriple=s390x-linux-gnu -mcpu=z13 | FileCheck %s
+
+; Test that a loaded value which is replicated is not inserted also in any
+; elements.
+
+; CHECK: vlvgp %v0, %r0, %r0
+; CHECK-NEXT: vrepf %v24, %v0, 1
+; CHECK-NOT: vlvgf %v24, %r0, 1
+; CHECK-NOT: vlvgf %v24, %r0, 2
+
+define <4 x i32> @fun(i32 %arg, i32* %dst) {
+ %tmp = load i32, i32* undef
+ %tmp8 = insertelement <4 x i32> undef, i32 %tmp, i32 0
+ %tmp9 = insertelement <4 x i32> %tmp8, i32 %tmp, i32 1
+ %tmp10 = insertelement <4 x i32> %tmp9, i32 %tmp, i32 2
+ %tmp11 = insertelement <4 x i32> %tmp10, i32 %arg, i32 3
+ store i32 %tmp, i32* %dst
+ ret <4 x i32> %tmp11
+}
+
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