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target/armv4_5: mark registers as 'save-restore'

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gdb uses this mark when creating a dummy frame for
manual call of a function by gdb command.
With the original setting all registers as caller_save = false
call command in gdb always clobbers r0, r1 and pc
and some other registers depending on the called function.

Set 'save-restore' for all registers but banked ones.

Change-Id: I16c49e4bf8001e38d18ce8861ca65988b08ccc88
Signed-off-by: Tomas Vanek <vanekt@fbl.cz>
Reviewed-on: https://review.openocd.org/c/openocd/+/9208
Reviewed-by: Antonio Borneo <borneo.antonio@gmail.com>
Tested-by: jenkins
This commit is contained in:
Tomas Vanek
2025-11-03 08:50:32 +01:00
parent d044affba5
commit 5d8a142703
1 changed files with 9 additions and 6 deletions
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15
src/target/armv4_5.c
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@@ -691,8 +691,6 @@ struct reg_cache *arm_build_reg_cache(struct target *target, struct arm *arm)
&& arm->core_type != ARM_CORE_TYPE_VIRT_EXT)
continue;
/* REVISIT handle Cortex-M, which only shadows R13/SP */
reg_arch_info[i].num = arm_core_regs[i].cookie;
reg_arch_info[i].mode = arm_core_regs[i].mode;
reg_arch_info[i].target = target;
@@ -706,9 +704,6 @@ struct reg_cache *arm_build_reg_cache(struct target *target, struct arm *arm)
reg_list[i].arch_info = &reg_arch_info[i];
reg_list[i].exist = true;
/* This really depends on the calling convention in use */
reg_list[i].caller_save = false;
/* Registers data type, as used by GDB target description */
reg_list[i].reg_data_type = malloc(sizeof(struct reg_data_type));
switch (arm_core_regs[i].cookie) {
@@ -729,9 +724,16 @@ struct reg_cache *arm_build_reg_cache(struct target *target, struct arm *arm)
if (reg_list[i].number <= 15 || reg_list[i].number == 25) {
reg_list[i].feature->name = "org.gnu.gdb.arm.core";
reg_list[i].group = "general";
/* Registers which should be preserved across GDB inferior function calls.
* Avoid saving banked registers as GDB (version 16.2 in time of writing)
* does not take the current mode into account and messes the value
* by restoring both the not banked register and the banked alias of it
* in the current mode. */
reg_list[i].caller_save = true;
} else {
reg_list[i].feature->name = "net.sourceforge.openocd.banked";
reg_list[i].group = "banked";
reg_list[i].caller_save = false;
}
cache->num_regs++;
@@ -751,7 +753,8 @@ struct reg_cache *arm_build_reg_cache(struct target *target, struct arm *arm)
reg_list[i].arch_info = &reg_arch_info[i];
reg_list[i].exist = true;
reg_list[i].caller_save = false;
/* Mark d0 - d31 and fpscr as save-restore for GDB */
reg_list[i].caller_save = true;
reg_list[i].reg_data_type = malloc(sizeof(struct reg_data_type));
reg_list[i].reg_data_type->type = arm_vfp_v3_regs[j].type;