[PATCH] [AArch64, record] Record FPSR for SIMD/FP data instructions

[PATCH] [AArch64, record] Record FPSR for SIMD/FP data instructions

[Luis Machado]

I noticed this failure in gdb.reverse/reverse-insn.exp:

FAIL: gdb.reverse/insn-reverse.exp: adv_simd_vect_shift: compare registers on insn 0:fcvtzs     s0, s0, #1

Turns out we're not recording changes to the FPSR.  The SIMD/FP data
instructions may set bits in the FPSR, so it needs to be recorded for
proper reverse operations.

gdb/ChangeLog:

YYYY-MM-DD  Luis Machado  <luis.machado@linaro.org>

	* aarch64-tdep.c (aarch64_record_data_proc_simd_fp): Record FPSR.
---
 gdb/aarch64-tdep.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/gdb/aarch64-tdep.c b/gdb/aarch64-tdep.c
index 40c73be502..5858b64970 100644
--- a/gdb/aarch64-tdep.c
+++ b/gdb/aarch64-tdep.c
@@ -4470,8 +4470,15 @@ aarch64_record_data_proc_simd_fp (insn_decode_record *aarch64_insn_r)
   if (record_debug)
     debug_printf ("\n");
 
+  /* Record the V/X register.  */
   aarch64_insn_r->reg_rec_count++;
-  gdb_assert (aarch64_insn_r->reg_rec_count == 1);
+
+  /* Some of these instructions may set bits in the FPSR, so record it
+     too.  */
+  record_buf[1] = AARCH64_FPSR_REGNUM;
+  aarch64_insn_r->reg_rec_count++;
+
+  gdb_assert (aarch64_insn_r->reg_rec_count == 2);
   REG_ALLOC (aarch64_insn_r->aarch64_regs, aarch64_insn_r->reg_rec_count,
 	     record_buf);
   return AARCH64_RECORD_SUCCESS;
-- 
2.25.1

Re: [PATCH] [AArch64, record] Record FPSR for SIMD/FP data instructions

[Luis Machado]

On 12/14/20 11:43 AM, Luis Machado wrote:
> I noticed this failure in gdb.reverse/reverse-insn.exp:
> 
> FAIL: gdb.reverse/insn-reverse.exp: adv_simd_vect_shift: compare registers on insn 0:fcvtzs     s0, s0, #1
> 
> Turns out we're not recording changes to the FPSR.  The SIMD/FP data
> instructions may set bits in the FPSR, so it needs to be recorded for
> proper reverse operations.
> 
> gdb/ChangeLog:
> 
> YYYY-MM-DD  Luis Machado  <luis.machado@linaro.org>
> 
> 	* aarch64-tdep.c (aarch64_record_data_proc_simd_fp): Record FPSR.
> ---
>   gdb/aarch64-tdep.c | 9 ++++++++-
>   1 file changed, 8 insertions(+), 1 deletion(-)
> 
> diff --git a/gdb/aarch64-tdep.c b/gdb/aarch64-tdep.c
> index 40c73be502..5858b64970 100644
> --- a/gdb/aarch64-tdep.c
> +++ b/gdb/aarch64-tdep.c
> @@ -4470,8 +4470,15 @@ aarch64_record_data_proc_simd_fp (insn_decode_record *aarch64_insn_r)
>     if (record_debug)
>       debug_printf ("\n");
>   
> +  /* Record the V/X register.  */
>     aarch64_insn_r->reg_rec_count++;
> -  gdb_assert (aarch64_insn_r->reg_rec_count == 1);
> +
> +  /* Some of these instructions may set bits in the FPSR, so record it
> +     too.  */
> +  record_buf[1] = AARCH64_FPSR_REGNUM;
> +  aarch64_insn_r->reg_rec_count++;
> +
> +  gdb_assert (aarch64_insn_r->reg_rec_count == 2);
>     REG_ALLOC (aarch64_insn_r->aarch64_regs, aarch64_insn_r->reg_rec_count,
>   	     record_buf);
>     return AARCH64_RECORD_SUCCESS;
> 

Pushed as bfbe4b84606cb9b8ac6f51b473b1d351924080aa.