Re: [PATCH v3 2/6] Implements support for recording thumb2 ASIMD struct ld/st insn

Will Newton
2014-08-13T14:10:44Z

On 13 August 2014 14:12, Omair Javaid <omair.javaid@linaro.org> wrote:
> gdb:
>
> 2014-08-13 Omair Javaid <omair.javaid@linaro.org>
>
> * arm-tdep.c (thumb2_record_asimd_struct_ld_st): Added record handler
> for advance SIMD struct ld/st insn.
> (thumb2_record_decode_insn_handler): Updated.
>
> ---
> gdb/arm-tdep.c | 192 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 191 insertions(+), 1 deletion(-)
>
> diff --git a/gdb/arm-tdep.c b/gdb/arm-tdep.c
> index 607b92e..adee197 100644
> --- a/gdb/arm-tdep.c
> +++ b/gdb/arm-tdep.c
> @@ -13048,6 +13048,196 @@ thumb2_record_coproc_insn (insn_decode_record *thumb2_insn_r)
> return arm_record_asimd_vfp_coproc (thumb2_insn_r);
> }
>
> +/* Record handler for advance SIMD structure load/store instructions. */
> +
> +static int
> +thumb2_record_asimd_struct_ld_st (insn_decode_record *thumb2_insn_r)
> +{
> + struct regcache *reg_cache = thumb2_insn_r->regcache;
> + uint32_t l_bit, a_bit, b_bits;
> + uint32_t record_buf[128], record_buf_mem[128];
> + uint32_t reg_rn, reg_vd, address, f_esize, f_elem;
> + uint32_t index_r = 0, index_e = 0, bf_regs = 0, index_m = 0, loop_t = 0;
> + uint8_t bf_align, f_ebytes;
> +
> + l_bit = bit (thumb2_insn_r->arm_insn, 21);
> + a_bit = bit (thumb2_insn_r->arm_insn, 23);
> + b_bits = bits (thumb2_insn_r->arm_insn, 8, 11);
> + bf_align = bits (thumb2_insn_r->arm_insn, 4, 5);

bf_align does not appear to be used.

> + reg_rn = bits (thumb2_insn_r->arm_insn, 16, 19);
> + reg_vd = bits (thumb2_insn_r->arm_insn, 12, 15);
> + reg_vd = (bit (thumb2_insn_r->arm_insn, 22) << 4) | reg_vd;
> + f_ebytes = (1 << bits (thumb2_insn_r->arm_insn, 6, 7));

The outer brackets are redundant.

> + f_esize = 8 * f_ebytes;
> + f_elem = 8 / f_ebytes;
> +
> + if (!l_bit)
> + {
> + ULONGEST u_regval = 0;
> + regcache_raw_read_unsigned (reg_cache, reg_rn, &u_regval);
> + address = u_regval;
> +
> + if (!a_bit)
> + {
> + /* Handle VST1. */
> + if (b_bits == 0x02 || b_bits == 0x0a || (b_bits & 0x0e) == 0x06)
> + {
> + if (b_bits == 0x07)
> + bf_regs = 1;
> + else if (b_bits == 0x0a)
> + bf_regs = 2;
> + else if (b_bits == 0x06)
> + bf_regs = 3;
> + else if (b_bits == 0x02)
> + bf_regs = 4;
> + else
> + bf_regs = 0;
> +
> + for (index_r = 0; index_r < bf_regs; index_r++)
> + {
> + for (index_e = 0; index_e < f_elem; index_e++)
> + {
> + record_buf_mem[index_m++] = f_ebytes;
> + record_buf_mem[index_m++] = address;
> + address = address + f_ebytes;
> + thumb2_insn_r->mem_rec_count += 1;
> + }
> + }
> + }
> + /* Handle VST2. */
> + else if (b_bits == 0x03 || (b_bits & 0x0e) == 0x08)
> + {
> + if (b_bits == 0x09 || b_bits == 0x08)
> + bf_regs = 1;
> + else if (b_bits == 0x03)
> + bf_regs = 2;
> + else
> + bf_regs = 0;
> +
> + for (index_r = 0; index_r < bf_regs; index_r++)
> + for (index_e = 0; index_e < f_elem; index_e++)
> + {
> + for (loop_t = 0; loop_t < 2; loop_t++)
> + {
> + record_buf_mem[index_m++] = f_ebytes;
> + record_buf_mem[index_m++] = address + (loop_t * f_ebytes);
> + thumb2_insn_r->mem_rec_count += 1;
> + }
> + address = address + (2 * f_ebytes);
> + }
> + }
> + /* Handle VST3. */
> + else if ((b_bits & 0x0e) == 0x04)
> + {
> + for (index_e = 0; index_e < f_elem; index_e++)
> + {
> + for (loop_t = 0; loop_t < 3; loop_t++)
> + {
> + record_buf_mem[index_m++] = f_ebytes;
> + record_buf_mem[index_m++] = address + (loop_t * f_ebytes);
> + thumb2_insn_r->mem_rec_count += 1;
> + }
> + address = address + (3 * f_ebytes);
> + }
> + }
> + /* Handle VST4. */
> + else if (!(b_bits & 0x0e))
> + {
> + for (index_e = 0; index_e < f_elem; index_e++)
> + {
> + for (loop_t = 0; loop_t < 4; loop_t++)
> + {
> + record_buf_mem[index_m++] = f_ebytes;
> + record_buf_mem[index_m++] = address + (loop_t * f_ebytes);
> + thumb2_insn_r->mem_rec_count += 1;
> + }
> + address = address + (4 * f_ebytes);
> + }
> + }
> + }
> + else
> + {
> + uint8_t bft_size = bits (thumb2_insn_r->arm_insn, 10, 11);
> +
> + if (bft_size == 0x00)
> + f_ebytes = 1;
> + else if (bft_size == 0x01)
> + f_ebytes = 2;
> + else if (bft_size == 0x02)
> + f_ebytes = 4;
> + else
> + f_ebytes = 0;
> +
> + /* Handle VST1. */
> + if (!(b_bits & 0x0b) || b_bits == 0x08)
> + thumb2_insn_r->mem_rec_count = 1;
> + /* Handle VST2. */
> + else if ((b_bits & 0x0b) == 0x01 || b_bits == 0x09)
> + thumb2_insn_r->mem_rec_count = 2;
> + /* Handle VST3. */
> + else if ((b_bits & 0x0b) == 0x02 || b_bits == 0x0a)
> + thumb2_insn_r->mem_rec_count = 3;
> + /* Handle VST4. */
> + else if ((b_bits & 0x0b) == 0x03 || b_bits == 0x0b)
> + thumb2_insn_r->mem_rec_count = 4;
> +
> + for (index_m = 0; index_m < thumb2_insn_r->mem_rec_count; index_m++)
> + {
> + record_buf_mem[index_m] = f_ebytes;
> + record_buf_mem[index_m] = address + (index_m * f_ebytes);
> + }
> + }
> + }
> + else
> + {
> + if (!a_bit)
> + {
> + /* Handle VLD1. */
> + if (b_bits == 0x02 || b_bits == 0x0a || (b_bits & 0x0e) == 0x06)
> + thumb2_insn_r->reg_rec_count = 1;
> + /* Handle VLD2. */
> + else if (b_bits == 0x03 || (b_bits & 0x0e) == 0x08)
> + thumb2_insn_r->reg_rec_count = 2;
> + /* Handle VLD3. */
> + else if ((b_bits & 0x0e) == 0x04)
> + thumb2_insn_r->reg_rec_count = 3;
> + /* Handle VLD4. */
> + else if (!(b_bits & 0x0e))
> + thumb2_insn_r->reg_rec_count = 4;
> + }
> + else
> + {
> + /* Handle VLD1. */
> + if (!(b_bits & 0x0b) || b_bits == 0x08 || b_bits == 0x0c)
> + thumb2_insn_r->reg_rec_count = 1;
> + /* Handle VLD2. */
> + else if ((b_bits & 0x0b) == 0x01 || b_bits == 0x09 || b_bits == 0x0d)
> + thumb2_insn_r->reg_rec_count = 2;
> + /* Handle VLD3. */
> + else if ((b_bits & 0x0b) == 0x02 || b_bits == 0x0a || b_bits == 0x0e)
> + thumb2_insn_r->reg_rec_count = 3;
> + /* Handle VLD4. */
> + else if ((b_bits & 0x0b) == 0x03 || b_bits == 0x0b || b_bits == 0x0f)
> + thumb2_insn_r->reg_rec_count = 4;
> +
> + for (index_r = 0; index_r < thumb2_insn_r->reg_rec_count; index_r++)
> + record_buf[index_r] = reg_vd + ARM_D0_REGNUM + index_r;
> + }
> + }
> +
> + if (bits (thumb2_insn_r->arm_insn, 0, 3) != 15)
> + {
> + record_buf[index_r] = reg_rn;
> + thumb2_insn_r->reg_rec_count += 1;
> + }
> +
> + REG_ALLOC (thumb2_insn_r->arm_regs, thumb2_insn_r->reg_rec_count,
> + record_buf);
> + MEM_ALLOC (thumb2_insn_r->arm_mems, thumb2_insn_r->mem_rec_count,
> + record_buf_mem);
> + return 0;
> +}
> +
> /* Decodes thumb2 instruction type and invokes its record handler. */
>
> static unsigned int
> @@ -13110,7 +13300,7 @@ thumb2_record_decode_insn_handler (insn_decode_record *thumb2_insn_r)
> else if (!((op2 & 0x71) ^ 0x10))
> {
> /* Advanced SIMD or structure load/store instructions. */
> - return arm_record_unsupported_insn (thumb2_insn_r);
> + return thumb2_record_asimd_struct_ld_st (thumb2_insn_r);
> }
> else if (!((op2 & 0x67) ^ 0x01))
> {
> --
> 1.9.1
>

--
Will Newton
Toolchain Working Group, Linaro