[PATCH] Implement support for recording arm/thumb mode coprocessor instructions

Omair Javaid
2014-08-28T09:50:24Z

gdb:

2014-08-13 Omair Javaid <omair.javaid@linaro.org>

* arm-tdep.c (arm_record_coproc_data_proc): Add record handler stubs
for asimd, vfp and coprocessor insns.
(arm_record_asimd_vfp_coproc): Add record handler for asimd, vfp
and coprocessor insns.
(thumb2_record_coproc_insn): New function.
(thumb2_record_decode_insn_handler): Update coprocessor insns record
handlers.
(decode_insn): Install arm_record_asimd_vfp_coproc as handler for
opcode 110 insns.

---
gdb/arm-tdep.c | 120 ++++++++++++++++++++++++++++++++++++++++++++++++++++-----
1 file changed, 110 insertions(+), 10 deletions(-)

diff --git a/gdb/arm-tdep.c b/gdb/arm-tdep.c
index 9bc6507..d659897 100644
--- a/gdb/arm-tdep.c
+++ b/gdb/arm-tdep.c
@@ -12022,20 +12022,78 @@ arm_record_unsupported_insn (insn_decode_record *arm_insn_r)
return -1;
}

+/* Handling opcode 110 insns. */
+
+static int
+arm_record_asimd_vfp_coproc (insn_decode_record *arm_insn_r)
+{
+ uint32_t op, op1, op1_sbit, op1_ebit, coproc;
+
+ coproc = bits (arm_insn_r->arm_insn, 8, 11);
+ op1 = bits (arm_insn_r->arm_insn, 20, 25);
+ op1_ebit = bit (arm_insn_r->arm_insn, 20);
+
+ if ((coproc & 0x0e) == 0x0a)
+ {
+ /* Handle extension register ld/st instructions. */
+ if (!(op1 & 0x20))
+ return arm_record_unsupported_insn (arm_insn_r);
+
+ /* 64-bit transfers between arm core and extension registers. */
+ if ((op1 & 0x3e) == 0x04)
+ return arm_record_unsupported_insn (arm_insn_r);
+ }
+ else
+ {
+ /* Handle coprocessor ld/st instructions. */
+ if (!(op1 & 0x3a))
+ {
+ /* Store. */
+ if (!op1_ebit)
+ return arm_record_unsupported_insn (arm_insn_r);
+ else
+ /* Load. */
+ return arm_record_unsupported_insn (arm_insn_r);
+ }
+
+ /* Move to coprocessor from two arm core registers. */
+ if (op1 == 0x4)
+ return arm_record_unsupported_insn (arm_insn_r);
+
+ /* Move to two arm core registers from coprocessor. */
+ if (op1 == 0x5)
+ {
+ uint32_t reg_t[2];
+
+ reg_t[0] = bits (arm_insn_r->arm_insn, 12, 15);
+ reg_t[1] = bits (arm_insn_r->arm_insn, 16, 19);
+ arm_insn_r->reg_rec_count = 2;
+
+ REG_ALLOC (arm_insn_r->arm_regs, arm_insn_r->reg_rec_count, reg_t);
+ return 0;
+ }
+ }
+ return arm_record_unsupported_insn (arm_insn_r);
+}
+
/* Handling opcode 111 insns. */

static int
arm_record_coproc_data_proc (insn_decode_record *arm_insn_r)
{
+ uint32_t op, op1_sbit, op1_ebit, coproc;
struct gdbarch_tdep *tdep = gdbarch_tdep (arm_insn_r->gdbarch);
struct regcache *reg_cache = arm_insn_r->regcache;
- uint32_t ret = 0; /* function return value: -1:record failure ; 0:success */
ULONGEST u_regval = 0;

arm_insn_r->opcode = bits (arm_insn_r->arm_insn, 24, 27);
+ coproc = bits (arm_insn_r->arm_insn, 8, 11);
+ op1_sbit = bit (arm_insn_r->arm_insn, 24);
+ op1_ebit = bit (arm_insn_r->arm_insn, 20);
+ op = bit (arm_insn_r->arm_insn, 4);

/* Handle arm SWI/SVC system call instructions. */
- if (15 == arm_insn_r->opcode)
+ if (op1_sbit)
{
if (tdep->arm_syscall_record != NULL)
{
@@ -12048,21 +12106,52 @@ arm_record_coproc_data_proc (insn_decode_record *arm_insn_r)
else /* EABI. */
regcache_raw_read_unsigned (reg_cache, 7, &svc_number);

- ret = tdep->arm_syscall_record (reg_cache, svc_number);
+ return tdep->arm_syscall_record (reg_cache, svc_number);
}
else
{
printf_unfiltered (_("no syscall record support\n"));
- ret = -1;
+ return -1;
}
}
+
+ if ((coproc & 0x0e) == 0x0a)
+ {
+ /* VFP data-processing instructions. */
+ if (!op1_sbit && !op)
+ return arm_record_unsupported_insn (arm_insn_r);
+
+ /* Advanced SIMD, VFP instructions. */
+ if (!op1_sbit && op)
+ return arm_record_unsupported_insn (arm_insn_r);
+ }
else
{
- arm_record_unsupported_insn (arm_insn_r);
- ret = -1;
+ /* Coprocessor data operations. */
+ if (!op1_sbit && !op)
+ return arm_record_unsupported_insn (arm_insn_r);
+
+ /* Move to Coprocessor from ARM core register. */
+ if (!op1_sbit && !op1_ebit && op)
+ return arm_record_unsupported_insn (arm_insn_r);
+
+ /* Move to arm core register from coprocessor. */
+ if (!op1_sbit && op1_ebit && op)
+ {
+ uint32_t record_buf[1];
+
+ record_buf[0] = bits (arm_insn_r->arm_insn, 12, 15);
+ if (record_buf[0] == 15)
+ record_buf[0] = ARM_PS_REGNUM;
+
+ arm_insn_r->reg_rec_count = 1;
+ REG_ALLOC (arm_insn_r->arm_regs, arm_insn_r->reg_rec_count,
+ record_buf);
+ return 0;
+ }
}

- return ret;
+ return arm_record_unsupported_insn (arm_insn_r);
}

/* Handling opcode 000 insns. */
@@ -12978,6 +13067,17 @@ thumb2_record_lmul_lmla_div (insn_decode_record *thumb2_insn_r)
return ARM_RECORD_SUCCESS;
}

+/* Record handler for thumb32 coprocessor instructions. */
+
+static int
+thumb2_record_coproc_insn (insn_decode_record *thumb2_insn_r)
+{
+ if (bit (thumb2_insn_r->arm_insn, 25))
+ return arm_record_coproc_data_proc (thumb2_insn_r);
+ else
+ return arm_record_asimd_vfp_coproc (thumb2_insn_r);
+}
+
/* Decodes thumb2 instruction type and invokes its record handler. */

static unsigned int
@@ -13009,7 +13109,7 @@ thumb2_record_decode_insn_handler (insn_decode_record *thumb2_insn_r)
else if (op2 & 0x40)
{
/* Co-processor instructions. */
- arm_record_unsupported_insn (thumb2_insn_r);
+ return thumb2_record_coproc_insn (thumb2_insn_r);
}
}
else if (op1 == 0x02)
@@ -13075,7 +13175,7 @@ thumb2_record_decode_insn_handler (insn_decode_record *thumb2_insn_r)
else if (op2 & 0x40)
{
/* Co-processor instructions. */
- return arm_record_unsupported_insn (thumb2_insn_r);
+ return thumb2_record_coproc_insn (thumb2_insn_r);
}
}

@@ -13119,7 +13219,7 @@ decode_insn (insn_decode_record *arm_record, record_type_t record_type,
arm_record_ld_st_reg_offset, /* 011. */
arm_record_ld_st_multiple, /* 100. */
arm_record_b_bl, /* 101. */
- arm_record_unsupported_insn, /* 110. */
+ arm_record_asimd_vfp_coproc, /* 110. */
arm_record_coproc_data_proc /* 111. */
};

--
1.9.1