gdb/riscv: Improve flen length determination

This solves an assertion failure when a remote provides a target
description which only refers to floating point registers by their
hardware name (e.g. f0), rather than their ABI name (e.g. ft0). GDB
assumed that should the floating point register feature be presented,
it would contain a register called ft0.

The floating point length is now instead determined by searching for
the same register, but looking for any of its aliases.

gdb/ChangeLog:

	* riscv-tdep.c (riscv_gdbarch_init): Support determining flen from
	target descriptions using exclusively floating point register name
	aliases.
This commit is contained in:
Simon Cook 2019-05-22 12:59:58 +01:00 committed by Andrew Burgess
parent 7166f90a77
commit 0a5954bd5f
2 changed files with 21 additions and 1 deletions

View File

@ -1,3 +1,9 @@
2019-05-22 Simon Cook <simon.cook@embecosm.com>
* riscv-tdep.c (riscv_gdbarch_init): Support determining flen from
target descriptions using exclusively floating point register name
aliases.
2019-05-21 Andrew Burgess <andrew.burgess@embecosm.com>
PR gdb/18644:

View File

@ -3094,7 +3094,21 @@ riscv_gdbarch_init (struct gdbarch_info info,
valid_p &= riscv_check_tdesc_feature (tdesc_data, feature_fpu,
&riscv_freg_feature);
int bitsize = tdesc_register_bitsize (feature_fpu, "ft0");
/* Search for the first floating point register (by any alias), to
determine the bitsize. */
int bitsize = -1;
const auto &fp0 = riscv_freg_feature.registers[0];
for (const char *name : fp0.names)
{
if (tdesc_unnumbered_register (feature_fpu, name))
{
bitsize = tdesc_register_bitsize (feature_fpu, name);
break;
}
}
gdb_assert (bitsize != -1);
features.flen = (bitsize / 8);
if (riscv_debug_gdbarch)