[llvm-commits] [llvm] r78297 - in /llvm/trunk: lib/Target/X86/X86ISelDAGToDAG.cpp test/CodeGen/X86/combiner-aa-0.ll

[Dan Gohman]

Author: djg
Date: Thu Aug  6 04:22:57 2009
New Revision: 78297

URL: http://llvm.org/viewvc/llvm-project?rev=78297&view=rev
Log:
Fix a bug in x86's PreprocessForRMW logic that was exposed
by aggressive chain operand optimization. UpdateNodeOperands
does not modify the node in place if it would result in
a node identical to an existing node.

Added:
    llvm/trunk/test/CodeGen/X86/combiner-aa-0.ll
Modified:
    llvm/trunk/lib/Target/X86/X86ISelDAGToDAG.cpp

Modified: llvm/trunk/lib/Target/X86/X86ISelDAGToDAG.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelDAGToDAG.cpp?rev=78297&r1=78296&r2=78297&view=diff

==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelDAGToDAG.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86ISelDAGToDAG.cpp Thu Aug  6 04:22:57 2009
@@ -342,9 +342,11 @@
       Ops.push_back(Load.getOperand(0));
     else
       Ops.push_back(TF.getOperand(i));
-  CurDAG->UpdateNodeOperands(TF, &Ops[0], Ops.size());
-  CurDAG->UpdateNodeOperands(Load, TF, Load.getOperand(1), Load.getOperand(2));
-  CurDAG->UpdateNodeOperands(Store, Load.getValue(1), Store.getOperand(1),
+  SDValue NewTF = CurDAG->UpdateNodeOperands(TF, &Ops[0], Ops.size());
+  SDValue NewLoad = CurDAG->UpdateNodeOperands(Load, NewTF,
+                                               Load.getOperand(1),
+                                               Load.getOperand(2));
+  CurDAG->UpdateNodeOperands(Store, NewLoad.getValue(1), Store.getOperand(1),
                              Store.getOperand(2), Store.getOperand(3));
 }
 

Added: llvm/trunk/test/CodeGen/X86/combiner-aa-0.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/combiner-aa-0.ll?rev=78297&view=auto

==============================================================================
--- llvm/trunk/test/CodeGen/X86/combiner-aa-0.ll (added)
+++ llvm/trunk/test/CodeGen/X86/combiner-aa-0.ll Thu Aug  6 04:22:57 2009
@@ -0,0 +1,20 @@
+; RUN: llvm-as < %s | llc -march=x86-64 -combiner-global-alias-analysis -combiner-alias-analysis
+
+target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128"
+	%struct.Hash_Key = type { [4 x i32], i32 }
+ at g_flipV_hashkey = external global %struct.Hash_Key, align 16		; <%struct.Hash_Key*> [#uses=1]
+
+define void @foo() nounwind {
+	%t0 = load i32* undef, align 16		; <i32> [#uses=1]
+	%t1 = load i32* null, align 4		; <i32> [#uses=1]
+	%t2 = srem i32 %t0, 32		; <i32> [#uses=1]
+	%t3 = shl i32 1, %t2		; <i32> [#uses=1]
+	%t4 = xor i32 %t3, %t1		; <i32> [#uses=1]
+	store i32 %t4, i32* null, align 4
+	%t5 = getelementptr %struct.Hash_Key* @g_flipV_hashkey, i64 0, i32 0, i64 0		; <i32*> [#uses=2]
+	%t6 = load i32* %t5, align 4		; <i32> [#uses=1]
+	%t7 = shl i32 1, undef		; <i32> [#uses=1]
+	%t8 = xor i32 %t7, %t6		; <i32> [#uses=1]
+	store i32 %t8, i32* %t5, align 4
+	unreachable
+}