[llvm-commits] CVS: llvm/lib/Target/X86/X86ISelPattern.cpp

[Chris Lattner]

Changes in directory llvm/lib/Target/X86:

X86ISelPattern.cpp updated: 1.52 -> 1.53
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Log message:

Codegen factor nodes more intelligently according to perceived register pressure.


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Diffs of the changes:  (+14 -2)

Index: llvm/lib/Target/X86/X86ISelPattern.cpp
diff -u llvm/lib/Target/X86/X86ISelPattern.cpp:1.52 llvm/lib/Target/X86/X86ISelPattern.cpp:1.53
--- llvm/lib/Target/X86/X86ISelPattern.cpp:1.52	Thu Jan 13 12:01:36 2005
+++ llvm/lib/Target/X86/X86ISelPattern.cpp	Thu Jan 13 13:56:00 2005
@@ -2088,8 +2088,20 @@
     assert(0 && "Node not handled yet!");
   case ISD::EntryToken: return;  // Noop
   case ISD::TokenFactor:
-    for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i)
-      Select(Node->getOperand(i));
+    if (Node->getNumOperands() == 2) {
+      bool OneFirst = 
+        getRegPressure(Node->getOperand(1))>getRegPressure(Node->getOperand(0));
+      Select(Node->getOperand(OneFirst));
+      Select(Node->getOperand(!OneFirst));
+    } else {
+      std::vector<std::pair<unsigned, unsigned> > OpsP;
+      for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i)
+        OpsP.push_back(std::make_pair(getRegPressure(Node->getOperand(i)), i));
+      std::sort(OpsP.begin(), OpsP.end());
+      std::reverse(OpsP.begin(), OpsP.end());
+      for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i)
+        Select(Node->getOperand(OpsP[i].second));
+    }
     return;
   case ISD::CopyToReg:
     if (getRegPressure(N.getOperand(0)) > getRegPressure(N.getOperand(1))) {