Lower FrameIndex operand of DEBUG_VALUE (specially) and

print it as a comment on X86.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93499 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/X86/AsmPrinter/X86MCInstLower.cpp b/lib/Target/X86/AsmPrinter/X86MCInstLower.cpp
index a4939af1b8e80046821fd727dfcafee8953e37c0..9ee118cdfd93588326315b2b549d4c8cda915494 100644 (file)
--- a/lib/Target/X86/AsmPrinter/X86MCInstLower.cpp
+++ b/lib/Target/X86/AsmPrinter/X86MCInstLower.cpp
@@ -25,6 +25,7 @@
 #include "llvm/Support/FormattedStream.h"
 #include "llvm/Support/Mangler.h"
 #include "llvm/ADT/SmallString.h"
+#include "llvm/Analysis/DebugInfo.h"
 using namespace llvm;
 
 
@@ -420,6 +421,25 @@ void X86AsmPrinter::printInstructionThroughMCStreamer(const MachineInstr *MI) {
   case TargetInstrInfo::GC_LABEL:
     printLabel(MI);
     return;
+  case TargetInstrInfo::DEBUG_VALUE: {
+    if (!VerboseAsm)
+      return;
+    O << '\t' << MAI->getCommentString() << "DEBUG_VALUE: ";
+    // cast away const; DIetc do not take const operands for some reason
+    DIVariable V((MDNode*)(MI->getOperand(2).getMetadata()));
+    O << V.getName();
+    O << " <- ";
+    if (MI->getOperand(0).getType()==MachineOperand::MO_Register)
+      printOperand(MI, 0);
+    else {
+      assert(MI->getOperand(0).getType()==MachineOperand::MO_Immediate);
+      int64_t imm = MI->getOperand(0).getImm();
+      O << '[' << ((imm<0) ? "EBP" : "ESP+") << imm << ']';
+    }
+    O << "+";
+    printOperand(MI, 1);
+    return;
+  }
   case TargetInstrInfo::INLINEASM:
     printInlineAsm(MI);
     return;

diff --git a/lib/Target/X86/X86RegisterInfo.cpp b/lib/Target/X86/X86RegisterInfo.cpp
index d96aafda603a77a6e9406cae975a3e945056c562..9bd96af6c7506c15ab879cfb8d47f2c94e386931 100644 (file)
--- a/lib/Target/X86/X86RegisterInfo.cpp
+++ b/lib/Target/X86/X86RegisterInfo.cpp
@@ -591,6 +591,15 @@ X86RegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
   int FrameIndex = MI.getOperand(i).getIndex();
   unsigned BasePtr;
 
+  // DEBUG_VALUE has a special representation, and is only robust enough to
+  // represent SP(or BP) +- offset addressing modes.  We rewrite the
+  // FrameIndex to be a constant; implicitly positive constants are relative
+  // to ESP and negative ones to EBP.
+  if (MI.getOpcode()==TargetInstrInfo::DEBUG_VALUE) {
+    MI.getOperand(i).ChangeToImmediate(getFrameIndexOffset(MF, FrameIndex));
+    return 0;
+  }
+
   if (needsStackRealignment(MF))
     BasePtr = (FrameIndex < 0 ? FramePtr : StackPtr);
   else