[llvm-commits] [llvm] r163036 - in /llvm/trunk: lib/Target/X86/X86ISelLowering.cpp test/CodeGen/X86/vec_shuffle-26.ll

[Manman Ren]

Author: mren
Date: Fri Aug 31 18:16:57 2012
New Revision: 163036

URL: http://llvm.org/viewvc/llvm-project?rev=163036&view=rev
Log:
SelectionDAG: when constructing VZEXT_LOAD from other loads, make sure its
output chain is correctly setup.

As an example, if the original load must happen before later stores, we need
to make sure the constructed VZEXT_LOAD is constrained to be before the stores.

rdar://11457792

Modified:
    llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
    llvm/trunk/test/CodeGen/X86/vec_shuffle-26.ll

Modified: llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelLowering.cpp?rev=163036&r1=163035&r2=163036&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86ISelLowering.cpp Fri Aug 31 18:16:57 2012
@@ -4977,6 +4977,18 @@
                                 LDBase->getAlignment(),
                                 false/*isVolatile*/, true/*ReadMem*/,
                                 false/*WriteMem*/);
+
+    // Make sure the newly-created LOAD is in the same position as LDBase in
+    // terms of dependency. We create a TokenFactor for LDBase and ResNode, and
+    // update uses of LDBase's output chain to use the TokenFactor.
+    if (LDBase->hasAnyUseOfValue(1)) {
+      SDValue NewChain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other,
+                             SDValue(LDBase, 1), SDValue(ResNode.getNode(), 1));
+      DAG.ReplaceAllUsesOfValueWith(SDValue(LDBase, 1), NewChain);
+      DAG.UpdateNodeOperands(NewChain.getNode(), SDValue(LDBase, 1),
+                             SDValue(ResNode.getNode(), 1));
+    }
+
     return DAG.getNode(ISD::BITCAST, DL, VT, ResNode);
   }
   return SDValue();

Modified: llvm/trunk/test/CodeGen/X86/vec_shuffle-26.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/vec_shuffle-26.ll?rev=163036&r1=163035&r2=163036&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/vec_shuffle-26.ll (original)
+++ llvm/trunk/test/CodeGen/X86/vec_shuffle-26.ll Fri Aug 31 18:16:57 2012
@@ -1,6 +1,4 @@
-; RUN: llc < %s -march=x86 -mattr=sse41 -o %t
-; RUN: grep unpcklps %t | count 1
-; RUN: grep unpckhps %t | count 3
+; RUN: llc < %s -march=x86 -mattr=sse41 | FileCheck %s
 
 ; Transpose example using the more generic vector shuffle. Return float8
 ; instead of float16
@@ -14,6 +12,11 @@
 
 define <8 x float> @__transpose2(<4 x float> %p0, <4 x float> %p1, <4 x float> %p2, <4 x float> %p3) nounwind {
 entry:
+; CHECK: transpose2
+; CHECK: unpckhps
+; CHECK: unpckhps
+; CHECK: unpcklps
+; CHECK: unpckhps
 	%unpcklps = shufflevector <4 x float> %p0, <4 x float> %p2, <4 x i32> < i32 0, i32 4, i32 1, i32 5 >		; <<4 x float>> [#uses=2]
 	%unpckhps = shufflevector <4 x float> %p0, <4 x float> %p2, <4 x i32> < i32 2, i32 6, i32 3, i32 7 >		; <<4 x float>> [#uses=2]
 	%unpcklps8 = shufflevector <4 x float> %p1, <4 x float> %p3, <4 x i32> < i32 0, i32 4, i32 1, i32 5 >		; <<4 x float>> [#uses=2]
@@ -27,3 +30,28 @@
 ;       %r3 = shufflevector <8 x float> %r1,  <8 x float> %r2,  <16 x i32> < i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7, i32 8, i32 9, i32 10, i32 11, i32 12, i32 13, i32 14, i32 15 >; 
 	ret <8 x float> %r2
 }
+
+define <2 x i64> @lo_hi_shift(float* nocapture %x, float* nocapture %y) nounwind {
+entry:
+; movhps should happen before extractps to assure it gets the correct value.
+; CHECK: lo_hi_shift
+; CHECK: movhps ([[BASEREG:%[a-z]+]]),
+; CHECK: extractps ${{[0-9]+}}, %xmm{{[0-9]+}}, {{[0-9]*}}([[BASEREG]])
+; CHECK: extractps ${{[0-9]+}}, %xmm{{[0-9]+}}, {{[0-9]*}}([[BASEREG]])
+  %v.i = bitcast float* %y to <4 x float>*
+  %0 = load <4 x float>* %v.i, align 1
+  %1 = bitcast float* %x to <1 x i64>*
+  %.val = load <1 x i64>* %1, align 1
+  %2 = bitcast <1 x i64> %.val to <2 x float>
+  %shuffle.i = shufflevector <2 x float> %2, <2 x float> undef, <4 x i32> <i32 0, i32 1, i32 undef, i32 undef>
+  %shuffle1.i = shufflevector <4 x float> %0, <4 x float> %shuffle.i, <4 x i32> <i32 0, i32 1, i32 4, i32 5>
+  %cast.i = bitcast <4 x float> %0 to <2 x i64>
+  %extract.i = extractelement <2 x i64> %cast.i, i32 1
+  %3 = bitcast float* %x to i64*
+  store i64 %extract.i, i64* %3, align 4
+  %4 = bitcast <4 x float> %0 to <16 x i8>
+  %5 = bitcast <4 x float> %shuffle1.i to <16 x i8>
+  %palignr = shufflevector <16 x i8> %5, <16 x i8> %4, <16 x i32> <i32 8, i32 9, i32 10, i32 11, i32 12, i32 13, i32 14, i32 15, i32 16, i32 17, i32 18, i32 19, i32 20, i32 21, i32 22, i32 23>
+  %6 = bitcast <16 x i8> %palignr to <2 x i64>
+  ret <2 x i64> %6
+}