[llvm-commits] [llvm] r69094 - in /llvm/trunk: lib/Target/X86/X86ISelDAGToDAG.cpp test/CodeGen/X86/h-registers-2.ll

[Dan Gohman]

Author: djg
Date: Tue Apr 14 17:45:05 2009
New Revision: 69094

URL: http://llvm.org/viewvc/llvm-project?rev=69094&view=rev
Log:
For the h-register addressing-mode trick, use the correct value for
any non-address uses of the address value. This fixes 186.crafty.

Added:
    llvm/trunk/test/CodeGen/X86/h-registers-2.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=69094&r1=69093&r2=69094&view=diff

==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelDAGToDAG.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86ISelDAGToDAG.cpp Tue Apr 14 17:45:05 2009
@@ -1049,6 +1049,9 @@
                                       X, Eight);
         SDValue And = CurDAG->getNode(ISD::AND, dl, N.getValueType(),
                                       Srl, Mask);
+        SDValue ShlCount = CurDAG->getConstant(ScaleLog, MVT::i8);
+        SDValue Shl = CurDAG->getNode(ISD::SHL, dl, N.getValueType(),
+                                      And, ShlCount);
 
         // Insert the new nodes into the topological ordering.
         if (Eight.getNode()->getNodeId() == -1 ||
@@ -1071,7 +1074,17 @@
           CurDAG->RepositionNode(N.getNode(), And.getNode());
           And.getNode()->setNodeId(N.getNode()->getNodeId());
         }
-        CurDAG->ReplaceAllUsesWith(N, And);
+        if (ShlCount.getNode()->getNodeId() == -1 ||
+            ShlCount.getNode()->getNodeId() > X.getNode()->getNodeId()) {
+          CurDAG->RepositionNode(X.getNode(), ShlCount.getNode());
+          ShlCount.getNode()->setNodeId(N.getNode()->getNodeId());
+        }
+        if (Shl.getNode()->getNodeId() == -1 ||
+            Shl.getNode()->getNodeId() > N.getNode()->getNodeId()) {
+          CurDAG->RepositionNode(N.getNode(), Shl.getNode());
+          Shl.getNode()->setNodeId(N.getNode()->getNodeId());
+        }
+        CurDAG->ReplaceAllUsesWith(N, Shl);
         AM.IndexReg = And;
         AM.Scale = (1 << ScaleLog);
         return false;

Added: llvm/trunk/test/CodeGen/X86/h-registers-2.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/h-registers-2.ll?rev=69094&view=auto

==============================================================================
--- llvm/trunk/test/CodeGen/X86/h-registers-2.ll (added)
+++ llvm/trunk/test/CodeGen/X86/h-registers-2.ll Tue Apr 14 17:45:05 2009
@@ -0,0 +1,15 @@
+; RUN: llvm-as < %s | llc -march=x86 > %t
+; grep {movzbl	%\[abcd\]h,} %t | count 1
+; grep {shll	\$3,} | count 1
+
+; Use an h register, but don't omit the explicit shift for
+; non-address use(s).
+
+define i32 @foo(i8* %x, i32 %y) nounwind {
+	%t0 = lshr i32 %y, 8		; <i32> [#uses=1]
+	%t1 = and i32 %t0, 255		; <i32> [#uses=2]
+        %t2 = shl i32 %t1, 3
+	%t3 = getelementptr i8* %x, i32 %t2		; <i8*> [#uses=1]
+	store i8 77, i8* %t3, align 4
+	ret i32 %t2
+}