Revert 100573, it's causing some testsuite problems.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100578 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/AsmPrinter/X86MCInstLower.cpp b/lib/Target/X86/AsmPrinter/X86MCInstLower.cpp
index 9b23408..a290eb0 100644
--- a/lib/Target/X86/AsmPrinter/X86MCInstLower.cpp
+++ b/lib/Target/X86/AsmPrinter/X86MCInstLower.cpp
@@ -326,10 +326,76 @@
   }
 }
 
+void X86AsmPrinter::PrintDebugValueComment(const MachineInstr *MI,
+                                           raw_ostream &O) {
+  // FIXME: if this is implemented for another target before it goes
+  // away completely, the common part should be moved into AsmPrinter.
+  O << '\t' << MAI->getCommentString() << "DEBUG_VALUE: ";
+  unsigned NOps = MI->getNumOperands();
+  // cast away const; DIetc do not take const operands for some reason.
+  DIVariable V((MDNode*)(MI->getOperand(NOps-1).getMetadata()));
+  O << V.getName();
+  O << " <- ";
+  if (NOps==3) {
+    // Register or immediate value. Register 0 means undef.
+    assert(MI->getOperand(0).isReg() ||
+           MI->getOperand(0).isImm() ||
+           MI->getOperand(0).isFPImm());
+    if (MI->getOperand(0).isReg() && MI->getOperand(0).getReg() == 0) {
+      // Suppress offset in this case, it is not meaningful.
+      O << "undef";
+      OutStreamer.AddBlankLine();
+      return;
+    }
+    
+    if (MI->getOperand(0).isFPImm()) {
+      // This is more naturally done in printOperand, but since the only use
+      // of such an operand is in this comment and that is temporary (and it's
+      // ugly), we prefer to keep this localized.
+      // The include of Type.h may be removable when this code is.
+      if (MI->getOperand(0).getFPImm()->getType()->isFloatTy() ||
+          MI->getOperand(0).getFPImm()->getType()->isDoubleTy())
+        MI->getOperand(0).print(O, &TM);
+      else {
+        // There is no good way to print long double.  Convert a copy to
+        // double.  Ah well, it's only a comment.
+        bool ignored;
+        APFloat APF = APFloat(MI->getOperand(0).getFPImm()->getValueAPF());
+        APF.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
+                    &ignored);
+        O << "(long double) " << APF.convertToDouble();
+      }
+    } else
+      printOperand(MI, 0, O);
+  } else {
+    if (MI->getOperand(0).isReg() && MI->getOperand(0).getReg() == 0) {
+      // Suppress offset in this case, it is not meaningful.
+      O << "undef";
+      OutStreamer.AddBlankLine();
+      return;
+    }
+    // Frame address.  Currently handles register +- offset only.
+    assert(MI->getOperand(0).isReg() && MI->getOperand(3).isImm());
+    O << '['; printOperand(MI, 0, O); O << '+'; printOperand(MI, 3, O);
+    O << ']';
+  }
+  O << "+";
+  printOperand(MI, NOps-2, O);
+}
+
+
 void X86AsmPrinter::EmitInstruction(const MachineInstr *MI) {
   X86MCInstLower MCInstLowering(OutContext, Mang, *this);
   switch (MI->getOpcode()) {
-
+  case TargetOpcode::DBG_VALUE:
+    if (isVerbose() && OutStreamer.hasRawTextSupport()) {
+      std::string TmpStr;
+      raw_string_ostream OS(TmpStr);
+      PrintDebugValueComment(MI, OS);
+      OutStreamer.EmitRawText(StringRef(OS.str()));
+    }
+    return;
+      
   case X86::MOVPC32r: {
     MCInst TmpInst;
     // This is a pseudo op for a two instruction sequence with a label, which