[2/2] PR 19051: support of inferior call with gnu vector support on ARM
Commit Message
This patch teaches GDB to support gnu vector in inferior calls. As a
result, fails in gdb.base/gnu_vector.exp are fixed. The calling
convention of gnu vector isn't documented in the AAPCS, because it
is the GCC extension. I checked the gcc/config/arm/arm.c, understand
how GCC pass arguments and return values, and do the same in GDB side.
The patch is tested with both hard float and soft float on arm-linux.
gdb:
2015-11-11 Yao Qi <yao.qi@linaro.org>
PR tdep/19051
* arm-tdep.c (arm_type_align): Return the right alignment
value for vector.
(arm_vfp_cprc_sub_candidate): Return true for 64-bit and
128-bit vector types.
(arm_return_in_memory): Handel vector type.
---
gdb/arm-tdep.c | 68 ++++++++++++++++++++++++++++++++++++++++++++++------------
1 file changed, 54 insertions(+), 14 deletions(-)
@@ -3446,8 +3446,18 @@ arm_type_align (struct type *t)
return TYPE_LENGTH (t);
case TYPE_CODE_ARRAY:
+ if (TYPE_VECTOR (t))
+ {
+ /* Use the natural alignment for vector types (the same for
+ scalar type), but the maximum alignment is 64-bit. */
+ if (TYPE_LENGTH (t) > 8)
+ return 8;
+ else
+ return TYPE_LENGTH (t);
+ }
+ else
+ return arm_type_align (TYPE_TARGET_TYPE (t));
case TYPE_CODE_COMPLEX:
- /* TODO: What about vector types? */
return arm_type_align (TYPE_TARGET_TYPE (t));
case TYPE_CODE_STRUCT:
@@ -3594,21 +3604,44 @@ arm_vfp_cprc_sub_candidate (struct type *t,
case TYPE_CODE_ARRAY:
{
- int count;
- unsigned unitlen;
- count = arm_vfp_cprc_sub_candidate (TYPE_TARGET_TYPE (t), base_type);
- if (count == -1)
- return -1;
- if (TYPE_LENGTH (t) == 0)
+ if (TYPE_VECTOR (t))
{
- gdb_assert (count == 0);
- return 0;
+ /* A 64-bit or 128-bit containerized vector type are VFP
+ CPRCs. */
+ switch (TYPE_LENGTH (t))
+ {
+ case 8:
+ if (*base_type == VFP_CPRC_UNKNOWN)
+ *base_type = VFP_CPRC_VEC64;
+ return 1;
+ case 16:
+ if (*base_type == VFP_CPRC_UNKNOWN)
+ *base_type = VFP_CPRC_VEC128;
+ return 1;
+ default:
+ return -1;
+ }
+ }
+ else
+ {
+ int count;
+ unsigned unitlen;
+
+ count = arm_vfp_cprc_sub_candidate (TYPE_TARGET_TYPE (t),
+ base_type);
+ if (count == -1)
+ return -1;
+ if (TYPE_LENGTH (t) == 0)
+ {
+ gdb_assert (count == 0);
+ return 0;
+ }
+ else if (count == 0)
+ return -1;
+ unitlen = arm_vfp_cprc_unit_length (*base_type);
+ gdb_assert ((TYPE_LENGTH (t) % unitlen) == 0);
+ return TYPE_LENGTH (t) / unitlen;
}
- else if (count == 0)
- return -1;
- unitlen = arm_vfp_cprc_unit_length (*base_type);
- gdb_assert ((TYPE_LENGTH (t) % unitlen) == 0);
- return TYPE_LENGTH (t) / unitlen;
}
break;
@@ -9002,6 +9035,13 @@ arm_return_in_memory (struct gdbarch *gdbarch, struct type *type)
&& TYPE_CODE_ARRAY != code && TYPE_CODE_COMPLEX != code)
return 0;
+ if (TYPE_CODE_ARRAY == code && TYPE_VECTOR (type))
+ {
+ /* Vector values should be returned using ARM registers if they
+ are not over 16 bytes. */
+ return (TYPE_LENGTH (type) > 16);
+ }
+
if (gdbarch_tdep (gdbarch)->arm_abi != ARM_ABI_APCS)
{
/* The AAPCS says all aggregates not larger than a word are returned