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

diff --git a/lib/CodeGen/RegAllocSimple.cpp b/lib/CodeGen/RegAllocSimple.cpp
index 4e6e1d2705e1b2e2793e6f3344cec7609f69865c..ad09f8220f8d2a37235a85903468324835605109 100644 (file)
--- a/lib/CodeGen/RegAllocSimple.cpp
+++ b/lib/CodeGen/RegAllocSimple.cpp
@@ -20,19 +20,25 @@
 #include "llvm/CodeGen/MachineInstr.h"
 #include "llvm/CodeGen/SSARegMap.h"
 #include "llvm/CodeGen/MachineFrameInfo.h"
+#include "llvm/CodeGen/RegAllocRegistry.h"
 #include "llvm/Target/TargetInstrInfo.h"
 #include "llvm/Target/TargetMachine.h"
 #include "llvm/Support/Debug.h"
+#include "llvm/Support/Compiler.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/ADT/STLExtras.h"
 #include <iostream>
 using namespace llvm;
 
 namespace {
-  Statistic<> NumStores("ra-simple", "Number of stores added");
-  Statistic<> NumLoads ("ra-simple", "Number of loads added");
+  static Statistic<> NumStores("ra-simple", "Number of stores added");
+  static Statistic<> NumLoads ("ra-simple", "Number of loads added");
 
-  class RegAllocSimple : public MachineFunctionPass {
+  static RegisterRegAlloc
+    simpleRegAlloc("simple", "  simple register allocator",
+                   createSimpleRegisterAllocator);
+
+  class VISIBILITY_HIDDEN RegAllocSimple : public MachineFunctionPass {
     MachineFunction *MF;
     const TargetMachine *TM;
     const MRegisterInfo *RegInfo;
@@ -165,12 +171,16 @@ void RegAllocSimple::AllocateBasicBlock(MachineBasicBlock &MBB) {
     unsigned Opcode = MI->getOpcode();
     const TargetInstrDescriptor &Desc = TM->getInstrInfo()->get(Opcode);
     const unsigned *Regs;
-    for (Regs = Desc.ImplicitUses; *Regs; ++Regs)
-      RegsUsed[*Regs] = true;
+    if (Desc.ImplicitUses) {
+      for (Regs = Desc.ImplicitUses; *Regs; ++Regs)
+        RegsUsed[*Regs] = true;
+    }
 
-    for (Regs = Desc.ImplicitDefs; *Regs; ++Regs) {
-      RegsUsed[*Regs] = true;
-      PhysRegsEverUsed[*Regs] = true;
+    if (Desc.ImplicitDefs) {
+      for (Regs = Desc.ImplicitDefs; *Regs; ++Regs) {
+        RegsUsed[*Regs] = true;
+        PhysRegsEverUsed[*Regs] = true;
+      }
     }
 
     // Loop over uses, move from memory into registers.
@@ -193,17 +203,13 @@ void RegAllocSimple::AllocateBasicBlock(MachineBasicBlock &MBB) {
               physReg = getFreeReg(virtualReg);
             } else {
               // must be same register number as the first operand
-              // This maps a = b + c into b += c, and saves b into a's spot
+              // This maps a = b + c into b = b + c, and saves b into a's spot.
               assert(MI->getOperand(1).isRegister()  &&
                      MI->getOperand(1).getReg() &&
                      MI->getOperand(1).isUse() &&
                      "Two address instruction invalid!");
 
               physReg = MI->getOperand(1).getReg();
-              spillVirtReg(MBB, next(MI), virtualReg, physReg);
-              MI->getOperand(1).setDef();
-              MI->RemoveOperand(0);
-              break; // This is the last operand to process
             }
             spillVirtReg(MBB, next(MI), virtualReg, physReg);
           } else {