diff options
Diffstat (limited to 'gdb/ax-gdb.c')
| -rw-r--r-- | gdb/ax-gdb.c | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/gdb/ax-gdb.c b/gdb/ax-gdb.c index 87aa210787..332840456f 100644 --- a/gdb/ax-gdb.c +++ b/gdb/ax-gdb.c @@ -2419,6 +2419,56 @@ ternop_cond_operation::do_generate_ax (struct expression *exp, value->kind = value2.kind; } +/* Generate code for GDB's magical `repeat' operator. + LVALUE @ INT creates an array INT elements long, and whose elements + have the same type as LVALUE, located in memory so that LVALUE is + its first element. For example, argv[0]@argc gives you the array + of command-line arguments. + + Unfortunately, because we have to know the types before we actually + have a value for the expression, we can't implement this perfectly + without changing the type system, having values that occupy two + stack slots, doing weird things with sizeof, etc. So we require + the right operand to be a constant expression. */ +void +repeat_operation::do_generate_ax (struct expression *exp, + struct agent_expr *ax, + struct axs_value *value, + struct type *cast_type) +{ + struct axs_value value1; + + /* We don't want to turn this into an rvalue, so no conversions + here. */ + std::get<0> (m_storage)->generate_ax (exp, ax, &value1); + if (value1.kind != axs_lvalue_memory) + error (_("Left operand of `@' must be an object in memory.")); + + /* Evaluate the length; it had better be a constant. */ + if (!std::get<1> (m_storage)->constant_p ()) + error (_("Right operand of `@' must be a " + "constant, in agent expressions.")); + + struct value *v + = std::get<1> (m_storage)->evaluate (nullptr, exp, + EVAL_AVOID_SIDE_EFFECTS); + if (value_type (v)->code () != TYPE_CODE_INT) + error (_("Right operand of `@' must be an integer.")); + int length = value_as_long (v); + if (length <= 0) + error (_("Right operand of `@' must be positive.")); + + /* The top of the stack is already the address of the object, so + all we need to do is frob the type of the lvalue. */ + /* FIXME-type-allocation: need a way to free this type when we are + done with it. */ + struct type *array + = lookup_array_range_type (value1.type, 0, length - 1); + + value->kind = axs_lvalue_memory; + value->type = array; +} + } /* This handles the middle-to-right-side of code generation for binary |