[llvm] r227248 - Revert "[x86] Combine x86mmx/i64 to v2i64 conversion to use scalar_to_vector"

Alexey Samsonov vonosmas at gmail.com
Tue Jan 27 13:34:12 PST 2015


Author: samsonov
Date: Tue Jan 27 15:34:11 2015
New Revision: 227248

URL: http://llvm.org/viewvc/llvm-project?rev=227248&view=rev
Log:
Revert "[x86] Combine x86mmx/i64 to v2i64 conversion to use scalar_to_vector"

This reverts commits r226953 and r226974.

Removed:
    llvm/trunk/test/CodeGen/X86/mmx-movq2dq.ll
Modified:
    llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
    llvm/trunk/test/CodeGen/X86/2012-01-18-vbitcast.ll
    llvm/trunk/test/CodeGen/X86/lower-bitcast.ll
    llvm/trunk/test/CodeGen/X86/widen_load-2.ll

Modified: llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelLowering.cpp?rev=227248&r1=227247&r2=227248&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86ISelLowering.cpp Tue Jan 27 15:34:11 2015
@@ -24761,8 +24761,6 @@ static SDValue PerformLOADCombine(SDNode
   LoadSDNode *Ld = cast<LoadSDNode>(N);
   EVT RegVT = Ld->getValueType(0);
   EVT MemVT = Ld->getMemoryVT();
-  SDValue Ptr   = Ld->getBasePtr();
-  SDValue Chain = Ld->getChain();
   SDLoc dl(Ld);
   const TargetLowering &TLI = DAG.getTargetLoweringInfo();
 
@@ -24801,33 +24799,6 @@ static SDValue PerformLOADCombine(SDNode
     return DCI.CombineTo(N, NewVec, TF, true);
   }
 
-  // Conversion from x86mmx/i64 to v2i64 types is often done via stack
-  // store/load. Under certain conditions we can bypass the memory access and
-  // combine this load to use a scalar_to_vector instead. This leads to
-  // a reduction in the stack use, redundant emission of shuffles and create
-  // isel matching candidates for movq2dq instructions.
-  if (RegVT == MVT::v2i64 && Subtarget->hasSSE2() && Ext == ISD::EXTLOAD &&
-      !Ld->isVolatile() && ISD::isNON_TRUNCStore(Chain.getNode())) {
-
-    // If this load is directly stored, get the original source value.
-    StoreSDNode *PrevST = cast<StoreSDNode>(Chain);
-    EVT SrcTy = PrevST->getValue().getValueType();
-    if (PrevST->getBasePtr() != Ptr ||
-        !(SrcTy == MVT::i64 || SrcTy == MVT::x86mmx))
-      return SDValue();
-    SDValue SrcVal = Chain.getOperand(1);
-
-    // On 32bit systems, we can't store 64bit integers, use f64 instead.
-    bool Usef64 = TLI.isTypeLegal(MVT::f64) && !Subtarget->is64Bit();
-    if (Usef64)
-      SrcVal = DAG.getNode(ISD::BITCAST, dl, MVT::f64, SrcVal);
-    SrcVal = DAG.getNode(ISD::SCALAR_TO_VECTOR, dl, Usef64 ? MVT::v2f64 : RegVT,
-                              SrcVal);
-
-    return DCI.CombineTo(N, Usef64 ?
-        DAG.getNode(ISD::BITCAST, dl, RegVT, SrcVal) : SrcVal, Chain);
-  }
-
   return SDValue();
 }
 

Modified: llvm/trunk/test/CodeGen/X86/2012-01-18-vbitcast.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/2012-01-18-vbitcast.ll?rev=227248&r1=227247&r2=227248&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/2012-01-18-vbitcast.ll (original)
+++ llvm/trunk/test/CodeGen/X86/2012-01-18-vbitcast.ll Tue Jan 27 15:34:11 2015
@@ -1,15 +1,14 @@
 ; RUN: llc < %s -march=x86-64 -mcpu=corei7 -mtriple=x86_64-pc-win32 | FileCheck %s
 
-; CHECK-LABEL: vcast:
+;CHECK-LABEL: vcast:
 define <2 x i32> @vcast(<2 x float> %a, <2 x float> %b) {
-; CHECK-NOT: pmovzxdq
-; CHECK-NOT: pmovzxdq
-; CHECK: movdqa (%{{.*}}),  %[[R0:xmm[0-9]+]]
+;CHECK: pmovzxdq
+;CHECK: pmovzxdq
   %af = bitcast <2 x float> %a to <2 x i32>
   %bf = bitcast <2 x float> %b to <2 x i32>
-; CHECK-NEXT: psubq (%{{.*}}), %[[R0]]
   %x = sub <2 x i32> %af, %bf
-; CHECK: ret
+;CHECK: psubq
   ret <2 x i32> %x
+;CHECK: ret
 }
 

Modified: llvm/trunk/test/CodeGen/X86/lower-bitcast.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/lower-bitcast.ll?rev=227248&r1=227247&r2=227248&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/lower-bitcast.ll (original)
+++ llvm/trunk/test/CodeGen/X86/lower-bitcast.ll Tue Jan 27 15:34:11 2015
@@ -68,13 +68,12 @@ define i64 @test4(i64 %A) {
   %2 = bitcast <2 x i32> %add to i64
   ret i64 %2
 }
-; FIXME: At the moment we still produce the sequence paddd+pshufd.
+; FIXME: At the moment we still produce the sequence pshufd+paddd+pshufd.
 ; Ideally, we should fold that sequence into a single paddd. This is fixed with
 ; the widening legalization.
 ;
 ; CHECK-LABEL: test4
-; CHECK: movd
-; CHECK-NOT: pshufd
+; CHECK: pshufd
 ; CHECK-NEXT: paddd
 ; CHECK-NEXT: pshufd
 ; CHECK: ret

Removed: llvm/trunk/test/CodeGen/X86/mmx-movq2dq.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/mmx-movq2dq.ll?rev=227247&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/X86/mmx-movq2dq.ll (original)
+++ llvm/trunk/test/CodeGen/X86/mmx-movq2dq.ll (removed)
@@ -1,29 +0,0 @@
-; RUN: llc < %s -march=x86 -mattr=+mmx,+sse2 | FileCheck %s -check-prefix=X86-32
-; RUN: llc < %s -march=x86-64 -mattr=+mmx,+sse2 | FileCheck %s -check-prefix=X86-64
-
-; X86-32-LABEL: test0
-; X86-64-LABEL: test0
-define i32 @test0(<1 x i64>* %v4) {
-  %v5 = load <1 x i64>* %v4, align 8
-  %v12 = bitcast <1 x i64> %v5 to <4 x i16>
-  %v13 = bitcast <4 x i16> %v12 to x86_mmx
-  ; X86-32: pshufw  $238
-  ; X86-32-NOT: movq
-  ; X86-32-NOT: movsd
-  ; X86-32: movq2dq
-  ; X86-64: pshufw  $238
-  ; X86-64-NOT: movq
-  ; X86-64-NOT: pshufd
-  ; X86-64: movq2dq
-  ; X86-64-NEXT: movd
-  %v14 = tail call x86_mmx @llvm.x86.sse.pshuf.w(x86_mmx %v13, i8 -18)
-  %v15 = bitcast x86_mmx %v14 to <4 x i16>
-  %v16 = bitcast <4 x i16> %v15 to <1 x i64>
-  %v17 = extractelement <1 x i64> %v16, i32 0
-  %v18 = bitcast i64 %v17 to <2 x i32>
-  %v19 = extractelement <2 x i32> %v18, i32 0
-  %v20 = add i32 %v19, 32
-  ret i32 %v20
-}
-
-declare x86_mmx @llvm.x86.sse.pshuf.w(x86_mmx, i8)

Modified: llvm/trunk/test/CodeGen/X86/widen_load-2.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/widen_load-2.ll?rev=227248&r1=227247&r2=227248&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/widen_load-2.ll (original)
+++ llvm/trunk/test/CodeGen/X86/widen_load-2.ll Tue Jan 27 15:34:11 2015
@@ -78,7 +78,8 @@ define void @add3i16(%i16vec3* nocapture
 ; CHECK-NEXT:    paddd    %[[R0]], %[[R1]]
 ; CHECK-NEXT:    pextrw   $4, %[[R1]], 4(%{{.*}})
 ; CHECK-NEXT:    pshufb   {{.*}}, %[[R1]]
-; CHECK-NEXT:    movd     %[[R1]], (%{{.*}})
+; CHECK-NEXT:    pmovzxdq %[[R1]], %[[R0]]
+; CHECK-NEXT:    movd     %[[R0]], (%{{.*}})
 	%a = load %i16vec3* %ap, align 16
 	%b = load %i16vec3* %bp, align 16
 	%x = add %i16vec3 %a, %b





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