[DWARF] Handle the DW_OP_entry_value operand

Add the IR and the AsmPrinter parts for handling of the DW_OP_entry_values
DWARF operation.

([11/13] Introduce the debug entry values.)

Co-authored-by: Ananth Sowda <asowda@cisco.com>
Co-authored-by: Nikola Prica <nikola.prica@rt-rk.com>
Co-authored-by: Ivan Baev <ibaev@cisco.com>

Differential Revision: https://reviews.llvm.org/D60866

llvm-svn: 364542

1 files changed, 17 insertions, 0 deletions

diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfExpression.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfExpression.cpp
index d483a30e499..2858afaa1cf 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfExpression.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfExpression.cpp
@@ -248,6 +248,10 @@ bool DwarfExpression::addMachineRegExpression(const TargetRegisterInfo &TRI,
         addReg(Reg.DwarfRegNo, Reg.Comment);
       addOpPiece(Reg.Size);
     }
+
+    if (isEntryValue() && DwarfVersion >= 4)
+      emitOp(dwarf::DW_OP_stack_value);
+
     DwarfRegs.clear();
     return true;
   }
@@ -296,6 +300,19 @@ bool DwarfExpression::addMachineRegExpression(const TargetRegisterInfo &TRI,
   return true;
 }
 
+void DwarfExpression::addEntryValueExpression(DIExpressionCursor &ExprCursor) {
+  auto Op = ExprCursor.take();
+  assert(Op && Op->getOp() == dwarf::DW_OP_entry_value);
+  assert(!isMemoryLocation() &&
+         "We don't support entry values of memory locations yet");
+
+  if (DwarfVersion >= 5)
+    emitOp(dwarf::DW_OP_entry_value);
+  else
+    emitOp(dwarf::DW_OP_GNU_entry_value);
+  emitUnsigned(Op->getArg(0));
+}
+
 /// Assuming a well-formed expression, match "DW_OP_deref* DW_OP_LLVM_fragment?".
 static bool isMemoryLocation(DIExpressionCursor ExprCursor) {
   while (ExprCursor) {