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Diffstat (limited to 'gdb/s390-tdep.c')
-rw-r--r--gdb/s390-tdep.c190
1 files changed, 104 insertions, 86 deletions
diff --git a/gdb/s390-tdep.c b/gdb/s390-tdep.c
index 7e36a28..1bc6fde 100644
--- a/gdb/s390-tdep.c
+++ b/gdb/s390-tdep.c
@@ -352,8 +352,14 @@ s390_pseudo_register_reggroup_p (struct gdbarch *gdbarch, int regnum,
{
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
- /* PC and CC pseudo registers need to be saved/restored in order to
- push or pop frames. */
+ /* We usually save/restore the whole PSW, which includes PC and CC.
+ However, some older gdbservers may not support saving/restoring
+ the whole PSW yet, and will return an XML register description
+ excluding those from the save/restore register groups. In those
+ cases, we still need to explicitly save/restore PC and CC in order
+ to push or pop frames. Since this doesn't hurt anything if we
+ already save/restore the whole PSW (it's just redundant), we add
+ PC and CC at this point unconditionally. */
if (group == save_reggroup || group == restore_reggroup)
return regnum == tdep->pc_regnum || regnum == tdep->cc_regnum;
@@ -1449,6 +1455,79 @@ s390_displaced_step_fixup (struct gdbarch *gdbarch,
paddress (gdbarch, regcache_read_pc (regs)));
}
+
+/* Helper routine to unwind pseudo registers. */
+
+static struct value *
+s390_unwind_pseudo_register (struct frame_info *this_frame, int regnum)
+{
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+ struct type *type = register_type (gdbarch, regnum);
+
+ /* Unwind PC via PSW address. */
+ if (regnum == tdep->pc_regnum)
+ {
+ struct value *val;
+
+ val = frame_unwind_register_value (this_frame, S390_PSWA_REGNUM);
+ if (!value_optimized_out (val))
+ {
+ LONGEST pswa = value_as_long (val);
+
+ if (TYPE_LENGTH (type) == 4)
+ return value_from_pointer (type, pswa & 0x7fffffff);
+ else
+ return value_from_pointer (type, pswa);
+ }
+ }
+
+ /* Unwind CC via PSW mask. */
+ if (regnum == tdep->cc_regnum)
+ {
+ struct value *val;
+
+ val = frame_unwind_register_value (this_frame, S390_PSWM_REGNUM);
+ if (!value_optimized_out (val))
+ {
+ LONGEST pswm = value_as_long (val);
+
+ if (TYPE_LENGTH (type) == 4)
+ return value_from_longest (type, (pswm >> 12) & 3);
+ else
+ return value_from_longest (type, (pswm >> 44) & 3);
+ }
+ }
+
+ /* Unwind full GPRs to show at least the lower halves (as the
+ upper halves are undefined). */
+ if (tdep->gpr_full_regnum != -1
+ && regnum >= tdep->gpr_full_regnum
+ && regnum < tdep->gpr_full_regnum + 16)
+ {
+ int reg = regnum - tdep->gpr_full_regnum;
+ struct value *val;
+
+ val = frame_unwind_register_value (this_frame, S390_R0_REGNUM + reg);
+ if (!value_optimized_out (val))
+ return value_cast (type, val);
+ }
+
+ return allocate_optimized_out_value (type);
+}
+
+static struct value *
+s390_trad_frame_prev_register (struct frame_info *this_frame,
+ struct trad_frame_saved_reg saved_regs[],
+ int regnum)
+{
+ if (regnum < S390_NUM_REGS)
+ return trad_frame_get_prev_register (this_frame, saved_regs, regnum);
+ else
+ return s390_unwind_pseudo_register (this_frame, regnum);
+}
+
+
/* Normal stack frames. */
struct s390_unwind_cache {
@@ -1465,7 +1544,6 @@ s390_prologue_frame_unwind_cache (struct frame_info *this_frame,
struct s390_unwind_cache *info)
{
struct gdbarch *gdbarch = get_frame_arch (this_frame);
- struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
int word_size = gdbarch_ptr_bit (gdbarch) / 8;
struct s390_prologue_data data;
pv_t *fp = &data.gpr[S390_FRAME_REGNUM - S390_R0_REGNUM];
@@ -1591,7 +1669,7 @@ s390_prologue_frame_unwind_cache (struct frame_info *this_frame,
trad_frame_set_unknown (info->saved_regs, i);
/* CC is always call-clobbered. */
- trad_frame_set_unknown (info->saved_regs, tdep->cc_regnum);
+ trad_frame_set_unknown (info->saved_regs, S390_PSWM_REGNUM);
/* Record the addresses of all register spill slots the prologue parser
has recognized. Consider only registers defined as call-saved by the
@@ -1609,16 +1687,16 @@ s390_prologue_frame_unwind_cache (struct frame_info *this_frame,
info->saved_regs[S390_F0_REGNUM + i].addr = cfa - data.fpr_slot[i];
/* Function return will set PC to %r14. */
- info->saved_regs[tdep->pc_regnum] = info->saved_regs[S390_RETADDR_REGNUM];
+ info->saved_regs[S390_PSWA_REGNUM] = info->saved_regs[S390_RETADDR_REGNUM];
/* In frameless functions, we unwind simply by moving the return
address to the PC. However, if we actually stored to the
save area, use that -- we might only think the function frameless
because we're in the middle of the prologue ... */
if (size == 0
- && !trad_frame_addr_p (info->saved_regs, tdep->pc_regnum))
+ && !trad_frame_addr_p (info->saved_regs, S390_PSWA_REGNUM))
{
- info->saved_regs[tdep->pc_regnum].realreg = S390_RETADDR_REGNUM;
+ info->saved_regs[S390_PSWA_REGNUM].realreg = S390_RETADDR_REGNUM;
}
/* Another sanity check: unless this is a frameless function,
@@ -1628,7 +1706,7 @@ s390_prologue_frame_unwind_cache (struct frame_info *this_frame,
if (size > 0)
{
if (!trad_frame_addr_p (info->saved_regs, S390_SP_REGNUM)
- || !trad_frame_addr_p (info->saved_regs, tdep->pc_regnum))
+ || !trad_frame_addr_p (info->saved_regs, S390_PSWA_REGNUM))
prev_sp = -1;
}
@@ -1649,7 +1727,6 @@ s390_backchain_frame_unwind_cache (struct frame_info *this_frame,
struct s390_unwind_cache *info)
{
struct gdbarch *gdbarch = get_frame_arch (this_frame);
- struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
int word_size = gdbarch_ptr_bit (gdbarch) / 8;
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
CORE_ADDR backchain;
@@ -1663,7 +1740,7 @@ s390_backchain_frame_unwind_cache (struct frame_info *this_frame,
trad_frame_set_unknown (info->saved_regs, i);
/* CC is always call-clobbered. */
- trad_frame_set_unknown (info->saved_regs, tdep->cc_regnum);
+ trad_frame_set_unknown (info->saved_regs, S390_PSWM_REGNUM);
/* Get the backchain. */
reg = get_frame_register_unsigned (this_frame, S390_SP_REGNUM);
@@ -1685,7 +1762,7 @@ s390_backchain_frame_unwind_cache (struct frame_info *this_frame,
info->saved_regs[S390_RETADDR_REGNUM].addr = backchain + 14*word_size;
/* Function return will set PC to %r14. */
- info->saved_regs[tdep->pc_regnum]
+ info->saved_regs[S390_PSWA_REGNUM]
= info->saved_regs[S390_RETADDR_REGNUM];
/* We use the current value of the frame register as local_base,
@@ -1739,28 +1816,10 @@ s390_frame_prev_register (struct frame_info *this_frame,
void **this_prologue_cache, int regnum)
{
struct gdbarch *gdbarch = get_frame_arch (this_frame);
- struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
struct s390_unwind_cache *info
= s390_frame_unwind_cache (this_frame, this_prologue_cache);
- /* Unwind full GPRs to show at least the lower halves (as the
- upper halves are undefined). */
- if (tdep->gpr_full_regnum != -1
- && regnum >= tdep->gpr_full_regnum
- && regnum < tdep->gpr_full_regnum + 16)
- {
- int reg = regnum - tdep->gpr_full_regnum + S390_R0_REGNUM;
- struct value *val, *newval;
-
- val = trad_frame_get_prev_register (this_frame, info->saved_regs, reg);
- newval = value_cast (register_type (gdbarch, regnum), val);
- if (value_optimized_out (val))
- set_value_optimized_out (newval, 1);
-
- return newval;
- }
-
- return trad_frame_get_prev_register (this_frame, info->saved_regs, regnum);
+ return s390_trad_frame_prev_register (this_frame, info->saved_regs, regnum);
}
static const struct frame_unwind s390_frame_unwind = {
@@ -1788,7 +1847,6 @@ s390_stub_frame_unwind_cache (struct frame_info *this_frame,
void **this_prologue_cache)
{
struct gdbarch *gdbarch = get_frame_arch (this_frame);
- struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
int word_size = gdbarch_ptr_bit (gdbarch) / 8;
struct s390_stub_unwind_cache *info;
ULONGEST reg;
@@ -1801,7 +1859,7 @@ s390_stub_frame_unwind_cache (struct frame_info *this_frame,
info->saved_regs = trad_frame_alloc_saved_regs (this_frame);
/* The return address is in register %r14. */
- info->saved_regs[tdep->pc_regnum].realreg = S390_RETADDR_REGNUM;
+ info->saved_regs[S390_PSWA_REGNUM].realreg = S390_RETADDR_REGNUM;
/* Retrieve stack pointer and determine our frame base. */
reg = get_frame_register_unsigned (this_frame, S390_SP_REGNUM);
@@ -1826,7 +1884,7 @@ s390_stub_frame_prev_register (struct frame_info *this_frame,
{
struct s390_stub_unwind_cache *info
= s390_stub_frame_unwind_cache (this_frame, this_prologue_cache);
- return trad_frame_get_prev_register (this_frame, info->saved_regs, regnum);
+ return s390_trad_frame_prev_register (this_frame, info->saved_regs, regnum);
}
static int
@@ -1875,7 +1933,6 @@ s390_sigtramp_frame_unwind_cache (struct frame_info *this_frame,
struct s390_sigtramp_unwind_cache *info;
ULONGEST this_sp, prev_sp;
CORE_ADDR next_ra, next_cfa, sigreg_ptr, sigreg_high_off;
- ULONGEST pswm;
int i;
if (*this_prologue_cache)
@@ -1928,16 +1985,6 @@ s390_sigtramp_frame_unwind_cache (struct frame_info *this_frame,
info->saved_regs[S390_PSWA_REGNUM].addr = sigreg_ptr;
sigreg_ptr += word_size;
- /* Point PC to PSWA as well. */
- info->saved_regs[tdep->pc_regnum] = info->saved_regs[S390_PSWA_REGNUM];
-
- /* Extract CC from PSWM. */
- pswm = read_memory_unsigned_integer (
- info->saved_regs[S390_PSWM_REGNUM].addr,
- word_size, byte_order);
- trad_frame_set_value (info->saved_regs, tdep->cc_regnum,
- (pswm >> (8 * word_size - 20)) & 3);
-
/* Then the GPRs. */
for (i = 0; i < 16; i++)
{
@@ -1972,22 +2019,6 @@ s390_sigtramp_frame_unwind_cache (struct frame_info *this_frame,
sigreg_ptr += 4;
}
- /* Provide read-only copies of the full registers. */
- if (tdep->gpr_full_regnum != -1)
- for (i = 0; i < 16; i++)
- {
- ULONGEST low, high;
- low = read_memory_unsigned_integer (
- info->saved_regs[S390_R0_REGNUM + i].addr,
- 4, byte_order);
- high = read_memory_unsigned_integer (
- info->saved_regs[S390_R0_UPPER_REGNUM + i].addr,
- 4, byte_order);
-
- trad_frame_set_value (info->saved_regs, tdep->gpr_full_regnum + i,
- (high << 32) | low);
- }
-
/* Restore the previous frame's SP. */
prev_sp = read_memory_unsigned_integer (
info->saved_regs[S390_SP_REGNUM].addr,
@@ -2015,7 +2046,7 @@ s390_sigtramp_frame_prev_register (struct frame_info *this_frame,
{
struct s390_sigtramp_unwind_cache *info
= s390_sigtramp_frame_unwind_cache (this_frame, this_prologue_cache);
- return trad_frame_get_prev_register (this_frame, info->saved_regs, regnum);
+ return s390_trad_frame_prev_register (this_frame, info->saved_regs, regnum);
}
static int
@@ -2098,17 +2129,7 @@ static struct value *
s390_dwarf2_prev_register (struct frame_info *this_frame, void **this_cache,
int regnum)
{
- struct gdbarch *gdbarch = get_frame_arch (this_frame);
- struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
- int reg = regnum - tdep->gpr_full_regnum;
- struct value *val, *newval;
-
- val = frame_unwind_register_value (this_frame, S390_R0_REGNUM + reg);
- newval = value_cast (register_type (gdbarch, regnum), val);
- if (value_optimized_out (val))
- set_value_optimized_out (newval, 1);
-
- return newval;
+ return s390_unwind_pseudo_register (this_frame, regnum);
}
static void
@@ -2118,9 +2139,17 @@ s390_dwarf2_frame_init_reg (struct gdbarch *gdbarch, int regnum,
{
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+ /* The condition code (and thus PSW mask) is call-clobbered. */
+ if (regnum == S390_PSWM_REGNUM)
+ reg->how = DWARF2_FRAME_REG_UNDEFINED;
+
+ /* The PSW address unwinds to the return address. */
+ else if (regnum == S390_PSWA_REGNUM)
+ reg->how = DWARF2_FRAME_REG_RA;
+
/* Fixed registers are call-saved or call-clobbered
depending on the ABI in use. */
- if (regnum >= 0 && regnum < S390_NUM_REGS)
+ else if (regnum < S390_NUM_REGS)
{
if (s390_register_call_saved (gdbarch, regnum))
reg->how = DWARF2_FRAME_REG_SAME_VALUE;
@@ -2128,19 +2157,8 @@ s390_dwarf2_frame_init_reg (struct gdbarch *gdbarch, int regnum,
reg->how = DWARF2_FRAME_REG_UNDEFINED;
}
- /* The CC pseudo register is call-clobbered. */
- else if (regnum == tdep->cc_regnum)
- reg->how = DWARF2_FRAME_REG_UNDEFINED;
-
- /* The PC register unwinds to the return address. */
- else if (regnum == tdep->pc_regnum)
- reg->how = DWARF2_FRAME_REG_RA;
-
- /* We install a special function to unwind full GPRs to show at
- least the lower halves (as the upper halves are undefined). */
- else if (tdep->gpr_full_regnum != -1
- && regnum >= tdep->gpr_full_regnum
- && regnum < tdep->gpr_full_regnum + 16)
+ /* We install a special function to unwind pseudos. */
+ else
{
reg->how = DWARF2_FRAME_REG_FN;
reg->loc.fn = s390_dwarf2_prev_register;