[PATCH v2 15/17] arm: Move insn_references_pc to common code

Antoine Tremblay
2016-06-09T12:57:32Z

This patch moves insn_references_pc to common code in arch/, so that it
can be used in gdbserver. It adds the arm_ prefix, since the function
is now exported.

gdb/ChangeLog:

* arm-tdep.c (arm_copy_preload): Adjust to renaming.
(arm_copy_preload_reg): Likewise.
(arm_copy_copro_load_store): Likewise.
(arm_copy_alu_imm): Likewise.
(arm_copy_alu_reg): Likewise.
(arm_copy_alu_shifted_reg): Likewise.
(arm_copy_extra_ld_st): Likewise.
(arm_copy_ldr_str_ldrb_strb): Likewise.
(insn_references_pc): Move to...
* arch/arm-insn-reloc.c (arm_insn_references_pc): ... here.
* arch/arm-insn-reloc.h (arm_insn_references_pc): New declaraction.
---
gdb/arch/arm-insn-reloc.c | 29 ++++++++++++++++++++++++++++
gdb/arch/arm-insn-reloc.h | 8 ++++++++
gdb/arm-tdep.c | 49 ++++++++---------------------------------------
3 files changed, 45 insertions(+), 41 deletions(-)

diff --git a/gdb/arch/arm-insn-reloc.c b/gdb/arch/arm-insn-reloc.c
index b6ede60..7ebb507 100644
--- a/gdb/arch/arm-insn-reloc.c
+++ b/gdb/arch/arm-insn-reloc.c
@@ -20,6 +20,35 @@
#include "arm.h"
#include "arm-insn-reloc.h"

+
+/* See arch/arm-insn-reloc.h. */
+
+int
+arm_insn_references_pc (uint32_t insn, uint32_t bitmask)
+{
+ uint32_t lowbit = 1;
+
+ while (bitmask != 0)
+ {
+ uint32_t mask;
+
+ for (; lowbit && (bitmask & lowbit) == 0; lowbit <<= 1)
+ ;
+
+ if (!lowbit)
+ break;
+
+ mask = lowbit * 0xf;
+
+ if ((insn & mask) == mask)
+ return 1;
+
+ bitmask &= ~mask;
+ }
+
+ return 0;
+}
+
static int
arm_decode_misc_memhint_neon (uint32_t insn,
struct arm_insn_reloc_visitor *visitor,
diff --git a/gdb/arch/arm-insn-reloc.h b/gdb/arch/arm-insn-reloc.h
index 6e83ad4..8f93214 100644
--- a/gdb/arch/arm-insn-reloc.h
+++ b/gdb/arch/arm-insn-reloc.h
@@ -84,6 +84,14 @@ struct thumb_16bit_insn_reloc_visitor
int (*svc) (uint16_t insn, struct arm_insn_reloc_data *data);
};

+/* This function is used to concisely determine if an instruction INSN
+ references PC. Register fields of interest in INSN should have the
+ corresponding fields of BITMASK set to 0b1111. The function
+ returns return 1 if any of these fields in INSN reference the PC
+ (also 0b1111, r15), else it returns 0. */
+
+extern int arm_insn_references_pc (uint32_t insn, uint32_t bitmask);
+
extern int arm_relocate_insn (uint32_t insn,
struct arm_insn_reloc_visitor *visitor,
struct arm_insn_reloc_data *data);
diff --git a/gdb/arm-tdep.c b/gdb/arm-tdep.c
index 2a83b82..32c81c2 100644
--- a/gdb/arm-tdep.c
+++ b/gdb/arm-tdep.c
@@ -4653,38 +4653,6 @@ displaced_write_reg (struct regcache *regs, struct displaced_step_closure *dsc,
}
}

-/* This function is used to concisely determine if an instruction INSN
- references PC. Register fields of interest in INSN should have the
- corresponding fields of BITMASK set to 0b1111. The function
- returns return 1 if any of these fields in INSN reference the PC
- (also 0b1111, r15), else it returns 0. */
-
-static int
-insn_references_pc (uint32_t insn, uint32_t bitmask)
-{
- uint32_t lowbit = 1;
-
- while (bitmask != 0)
- {
- uint32_t mask;
-
- for (; lowbit && (bitmask & lowbit) == 0; lowbit <<= 1)
- ;
-
- if (!lowbit)
- break;
-
- mask = lowbit * 0xf;
-
- if ((insn & mask) == mask)
- return 1;
-
- bitmask &= ~mask;
- }
-
- return 0;
-}
-
/* The simplest copy function. Many instructions have the same effect no
matter what address they are executed at: in those cases, use this. */

@@ -4773,7 +4741,7 @@ arm_copy_preload (uint32_t insn, struct arm_insn_reloc_data *data)
{
unsigned int rn = bits (insn, 16, 19);

- if (!insn_references_pc (insn, 0x000f0000ul))
+ if (!arm_insn_references_pc (insn, 0x000f0000ul))
return arm_copy_unmodified (insn, "preload", data);

if (debug_displaced)
@@ -4870,8 +4838,7 @@ arm_copy_preload_reg (uint32_t insn, struct arm_insn_reloc_data *data)
unsigned int rn = bits (insn, 16, 19);
unsigned int rm = bits (insn, 0, 3);

-
- if (!insn_references_pc (insn, 0x000f000ful))
+ if (!arm_insn_references_pc (insn, 0x000f000ful))
return arm_copy_unmodified (insn, "preload reg", data);

if (debug_displaced)
@@ -4932,7 +4899,7 @@ arm_copy_copro_load_store (uint32_t insn, struct arm_insn_reloc_data *data)
{
unsigned int rn = bits (insn, 16, 19);

- if (!insn_references_pc (insn, 0x000f0000ul))
+ if (!arm_insn_references_pc (insn, 0x000f0000ul))
return arm_copy_unmodified (insn, "copro load/store", data);

if (debug_displaced)
@@ -5238,7 +5205,7 @@ arm_copy_alu_imm (uint32_t insn, struct arm_insn_reloc_data *data)
int is_mov = (op == 0xd);
ULONGEST rd_val, rn_val;

- if (!insn_references_pc (insn, 0x000ff000ul))
+ if (!arm_insn_references_pc (insn, 0x000ff000ul))
return arm_copy_unmodified (insn, "ALU immediate", data);

if (debug_displaced)
@@ -5386,7 +5353,7 @@ arm_copy_alu_reg (uint32_t insn, struct arm_insn_reloc_data *data)
unsigned int op = bits (insn, 21, 24);
int is_mov = (op == 0xd);

- if (!insn_references_pc (insn, 0x000ff00ful))
+ if (!arm_insn_references_pc (insn, 0x000ff00ful))
return arm_copy_unmodified (insn, "ALU reg", data);

if (debug_displaced)
@@ -5487,7 +5454,7 @@ arm_copy_alu_shifted_reg (uint32_t insn, struct arm_insn_reloc_data *data)
int is_mov = (op == 0xd);
unsigned int rd, rn, rm, rs;

- if (!insn_references_pc (insn, 0x000fff0ful))
+ if (!arm_insn_references_pc (insn, 0x000fff0ful))
return arm_copy_unmodified (insn, "ALU shifted reg", data);

if (debug_displaced)
@@ -5581,7 +5548,7 @@ arm_copy_extra_ld_st (uint32_t insn, struct arm_insn_reloc_data *data,
struct displaced_step_closure *dsc = data->dsc;
struct regcache *regs = data->regs;

- if (!insn_references_pc (insn, 0x000ff00ful))
+ if (!arm_insn_references_pc (insn, 0x000ff00ful))
return arm_copy_unmodified (insn, "extra load/store", data);

if (debug_displaced)
@@ -5812,7 +5779,7 @@ arm_copy_ldr_str_ldrb_strb (uint32_t insn, struct arm_insn_reloc_data *data,
unsigned int rm = bits (insn, 0, 3); /* Only valid if !immed. */
struct displaced_step_closure *dsc = data->dsc;

- if (!insn_references_pc (insn, 0x000ff00ful))
+ if (!arm_insn_references_pc (insn, 0x000ff00ful))
return arm_copy_unmodified (insn, "load/store", data);

if (debug_displaced)
--
2.8.1