Commit 18649f48 authored by Oliver Stannard's avatar Oliver Stannard
Browse files

[llvm-objdump] Add entry_value and stack_value opcodes 

Add the DW_OP_entry_value and DW_OP_stack_value opcodes to the DWARF
expression printer.

Differential revision: https://reviews.llvm.org/D74843
parent c0cf5f5d

llvm/include/llvm/DebugInfo/DWARF/DWARFExpression.h

+4 −0
Original line number Diff line number Diff line
@@ -122,6 +122,10 @@ public: 
      return Op;

    }



    iterator skipBytes(uint64_t Add) {

      return iterator(Expr, Op.EndOffset + Add);

    }



    // Comparison operators are provided out of line.

    friend bool operator==(const iterator &, const iterator &);

  };

llvm/lib/DebugInfo/DWARF/DWARFExpression.cpp

+21 −0
Original line number Diff line number Diff line
@@ -401,6 +401,27 @@ static bool printCompactDWARFExpr(raw_ostream &OS, DWARFExpression::iterator I, 
        S << format("%+" PRId64, Offset);

      break;

    }

    case dwarf::DW_OP_entry_value:

    case dwarf::DW_OP_GNU_entry_value: {

      // DW_OP_entry_value contains a sub-expression which must be rendered

      // separately.

      uint64_t SubExprLength = Op.getRawOperand(0);

      DWARFExpression::iterator SubExprEnd = I.skipBytes(SubExprLength);

      ++I;

      raw_svector_ostream S(Stack.emplace_back().String);

      S << "entry(";

      printCompactDWARFExpr(S, I, SubExprEnd, MRI);

      S << ")";

      I = SubExprEnd;

      continue;

    }

    case dwarf::DW_OP_stack_value: {

      // The top stack entry should be treated as the actual value of tne

      // variable, rather than the address of the variable in memory.

      assert(!Stack.empty());

      Stack.back().Kind = PrintedExpr::Value;

      break;

    }

    default:

      if (Opcode >= dwarf::DW_OP_reg0 && Opcode <= dwarf::DW_OP_reg31) {

        // DW_OP_reg<N>: A register, with the register num implied by the

llvm/unittests/DebugInfo/DWARF/DWARFExpressionCompactPrinterTest.cpp

+15 −0
Original line number Diff line number Diff line
@@ -98,3 +98,18 @@ TEST_F(DWARFExpressionCompactPrinterTest, Test_OP_breg0_negative) { 
TEST_F(DWARFExpressionCompactPrinterTest, Test_OP_bregx) {

  TestExprPrinter({DW_OP_bregx, 0x0d, 0x28}, "[SP+40]");

}



TEST_F(DWARFExpressionCompactPrinterTest, Test_OP_stack_value) {

  TestExprPrinter({DW_OP_breg13, 0x04, DW_OP_stack_value}, "SP+4");

}



TEST_F(DWARFExpressionCompactPrinterTest, Test_OP_entry_value) {

  TestExprPrinter({DW_OP_entry_value, 0x01, DW_OP_reg0, DW_OP_stack_value},

                  "entry(R0)");

}



TEST_F(DWARFExpressionCompactPrinterTest, Test_OP_entry_value_mem) {

  TestExprPrinter(

      {DW_OP_entry_value, 0x02, DW_OP_breg13, 0x10, DW_OP_stack_value},

      "entry([SP+16])");

}