From: Zoran Zaric <Zoran.Zaric@amd.com>
Date: Wed, 14 Oct 2020 16:41:54 +0000 (+0100)
Subject: Remove DWARF expression composition check
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=087ced679c2644f893966d814a1efd2f84baee03;p=thirdparty%2Fbinutils-gdb.git

Remove DWARF expression composition check

The dwarf_expr_require_composition function reports an error if the
last operation is not a leaf node of the DWARF expression. This was
previously used to prevent location description operations to be used
freely in the DWARF expression.

With the new approach, all operations are treated the same and
everything is composable, so there is no need for the previous
restrictions in the expression evaluator.

gdb/ChangeLog:

	* dwarf2/expr.c (dwarf_expr_context::execute_stack_op): Remove
	the use of dwarf_expr_require_composition.
---

diff --git a/gdb/dwarf2/expr.c b/gdb/dwarf2/expr.c
index 2555f9969ef..676e0bae8a7 100644
--- a/gdb/dwarf2/expr.c
+++ b/gdb/dwarf2/expr.c
@@ -3308,7 +3308,6 @@ dwarf_expr_context::execute_stack_op (const gdb_byte *op_ptr,
 	    else
 	      result = op - DW_OP_reg0;
 
-	    dwarf_expr_require_composition (op_ptr, op_end, "DW_OP_reg");
 	    push (make_unique<dwarf_register> (arch, result));
 	    break;
 	  }
@@ -3324,8 +3323,6 @@ dwarf_expr_context::execute_stack_op (const gdb_byte *op_ptr,
 		    (arch, gdb::array_view<const gdb_byte> (op_ptr, len),
 		     BFD_ENDIAN_UNKNOWN));
 	    op_ptr += len;
-	    dwarf_expr_require_composition (op_ptr, op_end,
-					    "DW_OP_implicit_value");
 	    break;
 	  }
 
@@ -3337,9 +3334,6 @@ dwarf_expr_context::execute_stack_op (const gdb_byte *op_ptr,
 	    push (make_unique<dwarf_implicit>
 		    (arch, value->contents (),
 		     type_byte_order (value->type ())));
-
-	    dwarf_expr_require_composition (op_ptr, op_end,
-					    "DW_OP_stack_value");
 	    break;
 	  }
 
@@ -3364,8 +3358,6 @@ dwarf_expr_context::execute_stack_op (const gdb_byte *op_ptr,
 						       this->m_per_cu,
 						       this->m_addr_size,
 						       die_offset, len));
-	    dwarf_expr_require_composition (op_ptr, op_end,
-					    "DW_OP_implicit_pointer");
 	    break;
 	  }