Major calling convention code refactoring.

[oota-llvm.git] / lib / Target / X86 / X86FloatingPoint.cpp

diff --git a/lib/Target/X86/X86FloatingPoint.cpp b/lib/Target/X86/X86FloatingPoint.cpp
index 0f2fbcc986946a6becb6a2b6d2baba0c95986d8c..91a0a2a626f3ac5d44c97b10c0ebd8e088e7f7a0 100644 (file)
--- a/lib/Target/X86/X86FloatingPoint.cpp
+++ b/lib/Target/X86/X86FloatingPoint.cpp
@@ -31,19 +31,21 @@
 #define DEBUG_TYPE "x86-codegen"
 #include "X86.h"
 #include "X86InstrInfo.h"
+#include "llvm/ADT/DepthFirstIterator.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/ADT/STLExtras.h"
 #include "llvm/CodeGen/MachineFunctionPass.h"
 #include "llvm/CodeGen/MachineInstrBuilder.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
 #include "llvm/CodeGen/Passes.h"
+#include "llvm/Support/Compiler.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/raw_ostream.h"
 #include "llvm/Target/TargetInstrInfo.h"
 #include "llvm/Target/TargetMachine.h"
-#include "llvm/Support/Debug.h"
-#include "llvm/Support/Compiler.h"
-#include "llvm/ADT/DepthFirstIterator.h"
-#include "llvm/ADT/SmallPtrSet.h"
-#include "llvm/ADT/SmallVector.h"
-#include "llvm/ADT/Statistic.h"
-#include "llvm/ADT/STLExtras.h"
 #include <algorithm>
 using namespace llvm;
 
@@ -56,6 +58,7 @@ namespace {
     FPS() : MachineFunctionPass(&ID) {}
 
     virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+      AU.setPreservesCFG();
       AU.addPreservedID(MachineLoopInfoID);
       AU.addPreservedID(MachineDominatorsID);
       MachineFunctionPass::getAnalysisUsage(AU);
@@ -236,7 +239,7 @@ bool FPS::processBasicBlock(MachineFunction &MF, MachineBasicBlock &BB) {
       PrevMI = prior(I);
 
     ++NumFP;  // Keep track of # of pseudo instrs
-    DOUT << "\nFPInst:\t" << *MI;
+    DEBUG(errs() << "\nFPInst:\t" << *MI);
 
     // Get dead variables list now because the MI pointer may be deleted as part
     // of processing!
@@ -255,7 +258,7 @@ bool FPS::processBasicBlock(MachineFunction &MF, MachineBasicBlock &BB) {
     case X86II::CompareFP:  handleCompareFP(I); break;
     case X86II::CondMovFP:  handleCondMovFP(I); break;
     case X86II::SpecialFP:  handleSpecialFP(I); break;
-    default: assert(0 && "Unknown FP Type!");
+    default: llvm_unreachable("Unknown FP Type!");
     }
 
     // Check to see if any of the values defined by this instruction are dead
@@ -263,7 +266,7 @@ bool FPS::processBasicBlock(MachineFunction &MF, MachineBasicBlock &BB) {
     for (unsigned i = 0, e = DeadRegs.size(); i != e; ++i) {
       unsigned Reg = DeadRegs[i];
       if (Reg >= X86::FP0 && Reg <= X86::FP6) {
-        DOUT << "Register FP#" << Reg-X86::FP0 << " is dead!\n";
+        DEBUG(errs() << "Register FP#" << Reg-X86::FP0 << " is dead!\n");
         freeStackSlotAfter(I, Reg-X86::FP0);
       }
     }
@@ -945,7 +948,7 @@ void FPS::handleSpecialFP(MachineBasicBlock::iterator &I) {
   MachineInstr *MI = I;
   DebugLoc dl = MI->getDebugLoc();
   switch (MI->getOpcode()) {
-  default: assert(0 && "Unknown SpecialFP instruction!");
+  default: llvm_unreachable("Unknown SpecialFP instruction!");
   case X86::FpGET_ST0_32:// Appears immediately after a call returning FP type!
   case X86::FpGET_ST0_64:// Appears immediately after a call returning FP type!
   case X86::FpGET_ST0_80:// Appears immediately after a call returning FP type!
@@ -990,11 +993,21 @@ void FPS::handleSpecialFP(MachineBasicBlock::iterator &I) {
   }
   case X86::FpSET_ST0_32:
   case X86::FpSET_ST0_64:
-  case X86::FpSET_ST0_80:
-    assert((StackTop == 1 || StackTop == 2)
-           && "Stack should have one or two element on it to return!");
+  case X86::FpSET_ST0_80: {
+    unsigned Op0 = getFPReg(MI->getOperand(0));
+
+    // FpSET_ST0_80 is generated by copyRegToReg for both function return
+    // and inline assembly with the "st" constrain. In the latter case,
+    // it is possible for ST(0) to be alive after this instruction.
+    if (!MI->killsRegister(X86::FP0 + Op0)) {
+      // Duplicate Op0
+      duplicateToTop(0, 7 /*temp register*/, I);
+    } else {
+      moveToTop(Op0, I);
+    }
     --StackTop;   // "Forget" we have something on the top of stack!
     break;
+  }
   case X86::FpSET_ST1_32:
   case X86::FpSET_ST1_64:
   case X86::FpSET_ST1_80: