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| author | Tom Tromey <tromey@adacore.com> | 2021-01-06 13:47:48 -0700 |
|---|---|---|
| committer | Tom Tromey <tromey@adacore.com> | 2021-01-06 13:47:48 -0700 |
| commit | b49180acf205d8e52050cc05ca63f8f8630e7a9c (patch) | |
| tree | 97f6648672f7c041a7648101da8ff96eaa119db7 /gdb/ada-lang.c | |
| parent | 3c55062cc1d8fdb6788164a55c1e4b773c781985 (diff) | |
| download | fsf-binutils-gdb-b49180acf205d8e52050cc05ca63f8f8630e7a9c.zip fsf-binutils-gdb-b49180acf205d8e52050cc05ca63f8f8630e7a9c.tar.gz fsf-binutils-gdb-b49180acf205d8e52050cc05ca63f8f8630e7a9c.tar.bz2 | |
Fix fixed-point binary operation type handling
Testing showed that gdb was not correctly handling some fixed-point
binary operations correctly.
Addition and subtraction worked by casting the result to the type of
left hand operand. So, "fixed+int" had a different type -- and
different value -- from "int+fixed".
Furthermore, for multiplication and division, it does not make sense
to first cast both sides to the fixed-point type. For example, this
can prevent "f * 1" from yielding "f", if 1 is not in the domain of
"f". Instead, this patch changes gdb to use the value. (This is
somewhat different from Ada semantics, as those can yield a "universal
fixed point".)
This includes a new test case. It is only run in "minimal" mode, as
the old-style fixed point works differently, and is obsolete, so I
have no plans to change it.
gdb/ChangeLog
2021-01-06 Tom Tromey <tromey@adacore.com>
* ada-lang.c (ada_evaluate_subexp) <BINOP_ADD, BINOP_SUB>:
Do not cast result.
* valarith.c (fixed_point_binop): Handle multiplication
and division specially.
* valops.c (value_to_gdb_mpq): New function.
(value_cast_to_fixed_point): Use it.
gdb/testsuite/ChangeLog
2021-01-06 Tom Tromey <tromey@adacore.com>
* gdb.ada/fixed_points/pck.ads (Delta4): New constant.
(FP4_Type): New type.
(FP4_Var): New variable.
* gdb.ada/fixed_points/fixed_points.adb: Update.
* gdb.ada/fixed_points.exp: Add tests for binary operators.
Diffstat (limited to 'gdb/ada-lang.c')
| -rw-r--r-- | gdb/ada-lang.c | 58 |
1 files changed, 39 insertions, 19 deletions
diff --git a/gdb/ada-lang.c b/gdb/ada-lang.c index 8b20861..3bc7bdd 100644 --- a/gdb/ada-lang.c +++ b/gdb/ada-lang.c @@ -10195,18 +10195,28 @@ ada_evaluate_subexp (struct type *expect_type, struct expression *exp, return (value_from_longest (value_type (arg2), value_as_long (arg1) + value_as_long (arg2))); - if ((ada_is_gnat_encoded_fixed_point_type (value_type (arg1)) - || ada_is_gnat_encoded_fixed_point_type (value_type (arg2))) - && value_type (arg1) != value_type (arg2)) - error (_("Operands of fixed-point addition must have the same type")); - /* Do the addition, and cast the result to the type of the first - argument. We cannot cast the result to a reference type, so if - ARG1 is a reference type, find its underlying type. */ + /* Preserve the original type for use by the range case below. + We cannot cast the result to a reference type, so if ARG1 is + a reference type, find its underlying type. */ type = value_type (arg1); while (type->code () == TYPE_CODE_REF) type = TYPE_TARGET_TYPE (type); - binop_promote (exp->language_defn, exp->gdbarch, &arg1, &arg2); - return value_cast (type, value_binop (arg1, arg2, BINOP_ADD)); + if (ada_is_gnat_encoded_fixed_point_type (value_type (arg1)) + || ada_is_gnat_encoded_fixed_point_type (value_type (arg2))) + { + if (value_type (arg1) != value_type (arg2)) + error (_("Operands of fixed-point addition must have the same type")); + } + else + binop_promote (exp->language_defn, exp->gdbarch, &arg1, &arg2); + arg1 = value_binop (arg1, arg2, BINOP_ADD); + /* We need to special-case the result of adding to a range. + This is done for the benefit of "ptype". gdb's Ada support + historically used the LHS to set the result type here, so + preserve this behavior. */ + if (type->code () == TYPE_CODE_RANGE) + arg1 = value_cast (type, arg1); + return arg1; case BINOP_SUB: arg1 = evaluate_subexp_with_coercion (exp, pos, noside); @@ -10221,19 +10231,29 @@ ada_evaluate_subexp (struct type *expect_type, struct expression *exp, return (value_from_longest (value_type (arg2), value_as_long (arg1) - value_as_long (arg2))); - if ((ada_is_gnat_encoded_fixed_point_type (value_type (arg1)) - || ada_is_gnat_encoded_fixed_point_type (value_type (arg2))) - && value_type (arg1) != value_type (arg2)) - error (_("Operands of fixed-point subtraction " - "must have the same type")); - /* Do the substraction, and cast the result to the type of the first - argument. We cannot cast the result to a reference type, so if - ARG1 is a reference type, find its underlying type. */ + /* Preserve the original type for use by the range case below. + We cannot cast the result to a reference type, so if ARG1 is + a reference type, find its underlying type. */ type = value_type (arg1); while (type->code () == TYPE_CODE_REF) type = TYPE_TARGET_TYPE (type); - binop_promote (exp->language_defn, exp->gdbarch, &arg1, &arg2); - return value_cast (type, value_binop (arg1, arg2, BINOP_SUB)); + if (ada_is_gnat_encoded_fixed_point_type (value_type (arg1)) + || ada_is_gnat_encoded_fixed_point_type (value_type (arg2))) + { + if (value_type (arg1) != value_type (arg2)) + error (_("Operands of fixed-point subtraction " + "must have the same type")); + } + else + binop_promote (exp->language_defn, exp->gdbarch, &arg1, &arg2); + arg1 = value_binop (arg1, arg2, BINOP_SUB); + /* We need to special-case the result of adding to a range. + This is done for the benefit of "ptype". gdb's Ada support + historically used the LHS to set the result type here, so + preserve this behavior. */ + if (type->code () == TYPE_CODE_RANGE) + arg1 = value_cast (type, arg1); + return arg1; case BINOP_MUL: case BINOP_DIV: |