Rename LegalizeDAGTypes.cpp -> LegalizeTypes.cpp

[oota-llvm.git] / lib / CodeGen / BranchFolding.cpp

diff --git a/lib/CodeGen/BranchFolding.cpp b/lib/CodeGen/BranchFolding.cpp
index ad7d5fcc332485724028cafee1896f7fb204cc1c..d4b1e90fd54c8f530ba483edca7c8265f69a3800 100644 (file)
--- a/lib/CodeGen/BranchFolding.cpp
+++ b/lib/CodeGen/BranchFolding.cpp
@@ -46,7 +46,7 @@ namespace {
 
   struct BranchFolder : public MachineFunctionPass {
     static char ID;
-    BranchFolder(bool defaultEnableTailMerge) : 
+    explicit BranchFolder(bool defaultEnableTailMerge) : 
         MachineFunctionPass((intptr_t)&ID) {
           switch (FlagEnableTailMerge) {
           case cl::BOU_UNSET: EnableTailMerge = defaultEnableTailMerge; break;
@@ -271,7 +271,13 @@ static unsigned ComputeCommonTailLength(MachineBasicBlock *MBB1,
   unsigned TailLen = 0;
   while (I1 != MBB1->begin() && I2 != MBB2->begin()) {
     --I1; --I2;
-    if (!I1->isIdenticalTo(I2)) {
+    if (!I1->isIdenticalTo(I2) || 
+        // FIXME: This check is dubious. It's used to get around a problem where
+        // people incorrectly expect inline asm directives to remain in the same
+        // relative order. This is untenable because normal compiler
+        // optimizations (like this one) may reorder and/or merge these
+        // directives.
+        I1->getOpcode() == TargetInstrInfo::INLINEASM) {
       ++I1; ++I2;
       break;
     }
@@ -429,8 +435,14 @@ static bool MergeCompare(const std::pair<unsigned,MachineBasicBlock*> &p,
       return true;
     else if (p.second->getNumber() > q.second->getNumber())
       return false;
-    else
+    else {
+      // _GLIBCXX_DEBUG checks strict weak ordering, which involves comparing
+      // an object with itself.
+#ifndef _GLIBCXX_DEBUG
       assert(0 && "Predecessor appears twice");
+#endif
+      return(false);
+    }
 }
 
 // See if any of the blocks in MergePotentials (which all have a common single
@@ -978,17 +990,18 @@ void BranchFolder::OptimizeBlock(MachineBasicBlock *MBB) {
           }
 
           // Iterate through all the predecessors, revectoring each in-turn.
-          MachineBasicBlock::pred_iterator PI = MBB->pred_begin();
+          size_t PI = 0;
           bool DidChange = false;
           bool HasBranchToSelf = false;
-          while (PI != MBB->pred_end()) {
-            if (*PI == MBB) {
+          while(PI != MBB->pred_size()) {
+            MachineBasicBlock *PMBB = *(MBB->pred_begin() + PI);
+            if (PMBB == MBB) {
               // If this block has an uncond branch to itself, leave it.
               ++PI;
               HasBranchToSelf = true;
             } else {
               DidChange = true;
-              (*PI)->ReplaceUsesOfBlockWith(MBB, CurTBB);
+              PMBB->ReplaceUsesOfBlockWith(MBB, CurTBB);
             }
           }