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-rw-r--r--lib/CodeGen/SelectionDAG/DAGCombiner.cpp18
-rw-r--r--lib/CodeGen/SelectionDAG/SelectionDAG.cpp4
-rw-r--r--lib/Target/X86/X86ISelLowering.cpp27
-rwxr-xr-xtest/CodeGen/X86/avx-sext.ll68
-rwxr-xr-xtest/CodeGen/X86/avx2-conversions.ll12
5 files changed, 119 insertions, 10 deletions
diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index a82410ae6a..3e5a446e6e 100644
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -4298,11 +4298,19 @@ SDValue DAGCombiner::visitSIGN_EXTEND(SDNode *N) {
if (isa<ConstantSDNode>(N0))
return DAG.getNode(ISD::SIGN_EXTEND, N->getDebugLoc(), VT, N0);
- // fold (sext (sext x)) -> (sext x)
- // fold (sext (aext x)) -> (sext x)
- if (N0.getOpcode() == ISD::SIGN_EXTEND || N0.getOpcode() == ISD::ANY_EXTEND)
- return DAG.getNode(ISD::SIGN_EXTEND, N->getDebugLoc(), VT,
- N0.getOperand(0));
+ // Folding (sext (sext x)) is obvious, but we do it only after the type
+ // legalization phase. When the sequence is like {(T1->T2), (T2->T3)} and
+ // T1 or T3 (or the both) are illegal types, the TypeLegalizer may not
+ // give a good sequence for the (T1->T3) pair.
+ // So we give a chance to target specific combiner to optimize T1->T2 and T2->T3
+ // separately and may be fold them in a preceding of subsequent instruction.
+ if (Level >= AfterLegalizeTypes) {
+ // fold (sext (sext x)) -> (sext x)
+ // fold (sext (aext x)) -> (sext x)
+ if (N0.getOpcode() == ISD::SIGN_EXTEND || N0.getOpcode() == ISD::ANY_EXTEND)
+ return DAG.getNode(ISD::SIGN_EXTEND, N->getDebugLoc(), VT,
+ N0.getOperand(0));
+ }
if (N0.getOpcode() == ISD::TRUNCATE) {
// fold (sext (truncate (load x))) -> (sext (smaller load x))
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index 344d1447a8..91491bfe80 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -2554,9 +2554,7 @@ SDValue SelectionDAG::getNode(unsigned Opcode, DebugLoc DL,
VT.getVectorNumElements() ==
Operand.getValueType().getVectorNumElements()) &&
"Vector element count mismatch!");
- if (OpOpcode == ISD::SIGN_EXTEND || OpOpcode == ISD::ZERO_EXTEND)
- return getNode(OpOpcode, DL, VT, Operand.getNode()->getOperand(0));
- else if (OpOpcode == ISD::UNDEF)
+ if (OpOpcode == ISD::UNDEF)
// sext(undef) = 0, because the top bits will all be the same.
return getConstant(0, VT);
break;
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index f42884dd2e..a8294b6de9 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -16970,14 +16970,37 @@ static SDValue PerformVZEXT_MOVLCombine(SDNode *N, SelectionDAG &DAG) {
static SDValue PerformSExtCombine(SDNode *N, SelectionDAG &DAG,
TargetLowering::DAGCombinerInfo &DCI,
const X86Subtarget *Subtarget) {
+ EVT VT = N->getValueType(0);
+
+ if (!VT.isVector())
+ return SDValue();
+
+ SDValue In = N->getOperand(0);
+ EVT InVT = In.getValueType();
+ DebugLoc dl = N->getDebugLoc();
+ unsigned ExtenedEltSize = VT.getVectorElementType().getSizeInBits();
+
+ // Split SIGN_EXTEND operation to use vmovsx instruction when possible
+ if (InVT == MVT::v8i8) {
+ if (ExtenedEltSize > 16 && !Subtarget->hasInt256())
+ In = DAG.getNode(ISD::SIGN_EXTEND, dl, MVT::v8i16, In);
+ if (ExtenedEltSize > 32)
+ In = DAG.getNode(ISD::SIGN_EXTEND, dl, MVT::v8i32, In);
+ return DAG.getNode(ISD::SIGN_EXTEND, dl, VT, In);
+ }
+
+ if ((InVT == MVT::v4i8 || InVT == MVT::v4i16) &&
+ ExtenedEltSize > 32 && !Subtarget->hasInt256()) {
+ In = DAG.getNode(ISD::SIGN_EXTEND, dl, MVT::v4i32, In);
+ return DAG.getNode(ISD::SIGN_EXTEND, dl, VT, In);
+ }
if (!DCI.isBeforeLegalizeOps())
return SDValue();
if (!Subtarget->hasFp256())
return SDValue();
- EVT VT = N->getValueType(0);
- if (VT.isVector() && VT.getSizeInBits() == 256) {
+ if (VT.is256BitVector()) {
SDValue R = WidenMaskArithmetic(N, DAG, DCI, Subtarget);
if (R.getNode())
return R;
diff --git a/test/CodeGen/X86/avx-sext.ll b/test/CodeGen/X86/avx-sext.ll
index 8d7d79db7d..5201575f12 100755
--- a/test/CodeGen/X86/avx-sext.ll
+++ b/test/CodeGen/X86/avx-sext.ll
@@ -142,3 +142,71 @@ define <8 x i16> @load_sext_test6(<8 x i8> *%ptr) {
%Y = sext <8 x i8> %X to <8 x i16>
ret <8 x i16>%Y
}
+; AVX: sext_1
+; AVX: vpmovsxbd
+; AVX: vpmovsxdq
+; AVX: vpmovsxdq
+; AVX: ret
+define void @sext_1(<4 x i8>* %inbuf, <4 x i64>* %outbuf) {
+ %v0 = load <4 x i8>* %inbuf
+ %r = sext <4 x i8> %v0 to <4 x i64>
+ store <4 x i64> %r, <4 x i64>* %outbuf
+ ret void
+}
+
+; AVX: sext_2
+; AVX: vpmovsxbd
+; AVX: ret
+define void @sext_2(<4 x i8>* %inbuf, <4 x i32>* %outbuf) {
+ %v0 = load <4 x i8>* %inbuf
+ %r = sext <4 x i8> %v0 to <4 x i32>
+ store <4 x i32> %r, <4 x i32>* %outbuf
+ ret void
+}
+
+; AVX: sext_3
+; AVX: vpmovsxwd
+; AVX: ret
+define void @sext_3(<4 x i16>* %inbuf, <4 x i32>* %outbuf) {
+ %v0 = load <4 x i16>* %inbuf
+ %r = sext <4 x i16> %v0 to <4 x i32>
+ store <4 x i32> %r, <4 x i32>* %outbuf
+ ret void
+}
+
+; AVX: sext_4
+; AVX: vpmovsxwd
+; AVX: vpmovsxdq
+; AVX: vpmovsxdq
+; AVX: ret
+define void @sext_4(<4 x i16>* %inbuf, <4 x i64>* %outbuf) {
+ %v0 = load <4 x i16>* %inbuf
+ %r = sext <4 x i16> %v0 to <4 x i64>
+ store <4 x i64> %r, <4 x i64>* %outbuf
+ ret void
+}
+
+; AVX: sext_5
+; AVX: vpmovsxbw
+; AVX: vpmovsxwd
+; AVX: vpmovsxwd
+; AVX: vpmovsxdq
+; AVX: ret
+define void @sext_5(<8 x i8>* %inbuf, <8 x i64>* %outbuf) {
+ %v0 = load <8 x i8>* %inbuf
+ %r = sext <8 x i8> %v0 to <8 x i64>
+ store <8 x i64> %r, <8 x i64>* %outbuf
+ ret void
+}
+; AVX: sext_6
+; AVX: vpmovsxbw
+; AVX: vpmovsxwd
+; AVX: vpmovsxwd
+; AVX: ret
+define void @sext_6(<8 x i8>* %inbuf, <8 x i32>* %outbuf) {
+ %v0 = load <8 x i8>* %inbuf
+ %r = sext <8 x i8> %v0 to <8 x i32>
+ store <8 x i32> %r, <8 x i32>* %outbuf
+ ret void
+}
+
diff --git a/test/CodeGen/X86/avx2-conversions.ll b/test/CodeGen/X86/avx2-conversions.ll
index 3ce08dcc73..17bd10a76e 100755
--- a/test/CodeGen/X86/avx2-conversions.ll
+++ b/test/CodeGen/X86/avx2-conversions.ll
@@ -107,3 +107,15 @@ define <8 x i32> @load_sext_test5(<8 x i8> *%ptr) {
%Y = sext <8 x i8> %X to <8 x i32>
ret <8 x i32>%Y
}
+
+; CHECK: load_sext_test6
+; CHECK: vpmovsxbd (%r{{[^,]*}}), %ymm{{.*}}
+; CHECK: vpmovsxdq
+; CHECK: vpmovsxdq
+; CHECK: ret
+define <8 x i64> @load_sext_test6(<8 x i8> *%ptr) {
+ %X = load <8 x i8>* %ptr
+ %Y = sext <8 x i8> %X to <8 x i64>
+ ret <8 x i64>%Y
+}
+