[2/2,v2,AArch64] Recognize STR instruction in prologue
Commit Message
This patch teaches GDB AArch64 backend to recognize STR instructions
in prologue, like 'str x19, [sp, #-48]!' or 'str w0, [sp, #44]'.
The unit test is added too.
gdb:
2016-11-28 Yao Qi <yao.qi@linaro.org>
Pedro Alves <palves@redhat.com>
* aarch64-tdep.c (aarch64_analyze_prologue): Recognize STR
instruction.
(aarch64_analyze_prologue_test): More tests.
---
gdb/aarch64-tdep.c | 75 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 75 insertions(+)
Comments
Hi Yao,
On 12/01/2016 11:16 AM, Yao Qi wrote:
> + else if ((inst.opcode->iclass == ldst_imm9 /* Signed immediate. */
> + || (inst.opcode->iclass == ldst_pos /* Unsigned immediate. */
> + && (inst.opcode->op == OP_STR_POS
> + || inst.opcode->op == OP_STRF_POS)))
> + && inst.operands[1].addr.base_regno == AARCH64_SP_REGNUM
> + && strcmp ("str", inst.opcode->name) == 0)
> + {
> + /* STR (immediate) */
> + unsigned int rt = inst.operands[0].reg.regno;
> + int32_t imm = inst.operands[1].addr.offset.imm;
> + unsigned rn = inst.operands[1].addr.base_regno;
Mixed "unsigned int" vs "unsigned" style.
> + int is64
"bool".
> + = (aarch64_get_qualifier_esize (inst.operands[0].qualifier) == 8);
> + gdb_assert (inst.operands[0].type == AARCH64_OPND_Rt
> + || inst.operands[0].type == AARCH64_OPND_Ft);
> +
> + if (inst.operands[0].type == AARCH64_OPND_Ft)
> + {
> + /* Only bottom 64-bit of each V register (D register) need
> + to be preserved. */
> + gdb_assert (inst.operands[0].qualifier == AARCH64_OPND_QLF_S_D);
> + rt += AARCH64_X_REGISTER_COUNT;
> + }
> +
> + pv_area_store (stack, pv_add_constant (regs[rn], imm),
> + is64 ? 8 : 4, regs[rt]);
> + if (inst.operands[1].addr.writeback)
> + regs[rn] = pv_add_constant (regs[rn], imm);
> + }
> else if (inst.opcode->iclass == testbranch)
> {
> /* Stop analysis on branch. */
> @@ -546,6 +575,52 @@ aarch64_analyze_prologue_test (void)
> == -1);
> }
> }
> +
> + /* Test a prologue in which STR is used and frame pointer is not
> + used. */
Thanks for the new comments. This helps.
> + {
> + struct aarch64_prologue_cache cache;
> + cache.saved_regs = trad_frame_alloc_saved_regs (gdbarch);
> +
> + const uint32_t insns[] = {
"static const". Sorry, my fault.
Othewrise, code-style-wise LGTM. Thanks much for updating.
I've not payed attention to Aarch64-specifics, TBC. I just
assume you got those right. :-)
Thanks,
Pedro Alves
@@ -395,6 +395,35 @@ aarch64_analyze_prologue (struct gdbarch *gdbarch,
regs[rn] = pv_add_constant (regs[rn], imm);
}
+ else if ((inst.opcode->iclass == ldst_imm9 /* Signed immediate. */
+ || (inst.opcode->iclass == ldst_pos /* Unsigned immediate. */
+ && (inst.opcode->op == OP_STR_POS
+ || inst.opcode->op == OP_STRF_POS)))
+ && inst.operands[1].addr.base_regno == AARCH64_SP_REGNUM
+ && strcmp ("str", inst.opcode->name) == 0)
+ {
+ /* STR (immediate) */
+ unsigned int rt = inst.operands[0].reg.regno;
+ int32_t imm = inst.operands[1].addr.offset.imm;
+ unsigned rn = inst.operands[1].addr.base_regno;
+ int is64
+ = (aarch64_get_qualifier_esize (inst.operands[0].qualifier) == 8);
+ gdb_assert (inst.operands[0].type == AARCH64_OPND_Rt
+ || inst.operands[0].type == AARCH64_OPND_Ft);
+
+ if (inst.operands[0].type == AARCH64_OPND_Ft)
+ {
+ /* Only bottom 64-bit of each V register (D register) need
+ to be preserved. */
+ gdb_assert (inst.operands[0].qualifier == AARCH64_OPND_QLF_S_D);
+ rt += AARCH64_X_REGISTER_COUNT;
+ }
+
+ pv_area_store (stack, pv_add_constant (regs[rn], imm),
+ is64 ? 8 : 4, regs[rt]);
+ if (inst.operands[1].addr.writeback)
+ regs[rn] = pv_add_constant (regs[rn], imm);
+ }
else if (inst.opcode->iclass == testbranch)
{
/* Stop analysis on branch. */
@@ -546,6 +575,52 @@ aarch64_analyze_prologue_test (void)
== -1);
}
}
+
+ /* Test a prologue in which STR is used and frame pointer is not
+ used. */
+ {
+ struct aarch64_prologue_cache cache;
+ cache.saved_regs = trad_frame_alloc_saved_regs (gdbarch);
+
+ const uint32_t insns[] = {
+ 0xf81d0ff3, /* str x19, [sp, #-48]! */
+ 0xb9002fe0, /* str w0, [sp, #44] */
+ 0xf90013e1, /* str x1, [sp, #32]*/
+ 0xfd000fe0, /* str d0, [sp, #24] */
+ 0xaa0203f3, /* mov x19, x2 */
+ 0xf94013e0, /* ldr x0, [sp, #32] */
+ };
+ instruction_reader_test reader (insns);
+
+ CORE_ADDR end = aarch64_analyze_prologue (gdbarch, 0, 128, &cache, reader);
+
+ SELF_CHECK (end == 4 * 5);
+
+ SELF_CHECK (cache.framereg == AARCH64_SP_REGNUM);
+ SELF_CHECK (cache.framesize == 48);
+
+ for (int i = 0; i < AARCH64_X_REGISTER_COUNT; i++)
+ {
+ if (i == 1)
+ SELF_CHECK (cache.saved_regs[i].addr == -16);
+ else if (i == 19)
+ SELF_CHECK (cache.saved_regs[i].addr == -48);
+ else
+ SELF_CHECK (cache.saved_regs[i].addr == -1);
+ }
+
+ for (int i = 0; i < AARCH64_D_REGISTER_COUNT; i++)
+ {
+ int regnum = gdbarch_num_regs (gdbarch);
+
+ if (i == 0)
+ SELF_CHECK (cache.saved_regs[i + regnum + AARCH64_D0_REGNUM].addr
+ == -24);
+ else
+ SELF_CHECK (cache.saved_regs[i + regnum + AARCH64_D0_REGNUM].addr
+ == -1);
+ }
+ }
}
}
#endif /* GDB_SELF_TEST */