summaryrefslogtreecommitdiff
path: root/gdb/mips-tdep.c
diff options
context:
space:
mode:
Diffstat (limited to 'gdb/mips-tdep.c')
-rw-r--r--gdb/mips-tdep.c194
1 files changed, 121 insertions, 73 deletions
diff --git a/gdb/mips-tdep.c b/gdb/mips-tdep.c
index c072bf0be67..5a5a7164336 100644
--- a/gdb/mips-tdep.c
+++ b/gdb/mips-tdep.c
@@ -340,6 +340,15 @@ make_compact_addr (CORE_ADDR addr)
return ((addr) | (CORE_ADDR) 1);
}
+/* Extern version of unmake_compact_addr; we use a separate function
+ so that unmake_compact_addr can be inlined throughout this file. */
+
+CORE_ADDR
+mips_unmake_compact_addr (CORE_ADDR addr)
+{
+ return unmake_compact_addr (addr);
+}
+
/* Functions for setting and testing a bit in a minimal symbol that
marks it as MIPS16 or microMIPS function. The MSB of the minimal
symbol's "info" field is used for this purpose.
@@ -369,9 +378,15 @@ mips_elf_make_msymbol_special (asymbol * sym, struct minimal_symbol *msym)
return;
if (ELF_ST_IS_MICROMIPS (st_other))
- MSYMBOL_TARGET_FLAG_2 (msym) = 1;
+ {
+ MSYMBOL_TARGET_FLAG_2 (msym) = 1;
+ SET_MSYMBOL_VALUE_ADDRESS (msym, MSYMBOL_VALUE_RAW_ADDRESS (msym) | 1);
+ }
else if (ELF_ST_IS_MIPS16 (st_other))
- MSYMBOL_TARGET_FLAG_1 (msym) = 1;
+ {
+ MSYMBOL_TARGET_FLAG_1 (msym) = 1;
+ SET_MSYMBOL_VALUE_ADDRESS (msym, MSYMBOL_VALUE_RAW_ADDRESS (msym) | 1);
+ }
}
/* Return one iff MSYM refers to standard ISA code. */
@@ -398,6 +413,35 @@ msymbol_is_micromips (struct minimal_symbol *msym)
return MSYMBOL_TARGET_FLAG_2 (msym);
}
+/* Set the ISA bit in the main symbol too, complementing the corresponding
+ minimal symbol setting and reflecting the run-time value of the symbol.
+ The need for comes from the ISA bit having been cleared as code in
+ `_bfd_mips_elf_symbol_processing' separated it into the ELF symbol's
+ `st_other' STO_MIPS16 or STO_MICROMIPS annotation, making the values
+ of symbols referring to compressed code different in GDB to the values
+ used by actual code. That in turn makes them evaluate incorrectly in
+ expressions, producing results different to what the same expressions
+ yield when compiled into the program being debugged. */
+
+static void
+mips_make_symbol_special (struct symbol *sym, struct objfile *objfile)
+{
+ if (SYMBOL_CLASS (sym) == LOC_BLOCK)
+ {
+ /* We are in symbol reading so it is OK to cast away constness. */
+ struct block *block = (struct block *) SYMBOL_BLOCK_VALUE (sym);
+ CORE_ADDR compact_block_start;
+ struct bound_minimal_symbol msym;
+
+ compact_block_start = BLOCK_START (block) | 1;
+ msym = lookup_minimal_symbol_by_pc (compact_block_start);
+ if (msym.minsym && !msymbol_is_mips (msym.minsym))
+ {
+ BLOCK_START (block) = compact_block_start;
+ }
+ }
+}
+
/* XFER a value from the big/little/left end of the register.
Depending on the size of the value it might occupy the entire
register or just part of it. Make an allowance for this, aligning
@@ -1132,7 +1176,7 @@ mips_pc_is_mips (CORE_ADDR memaddr)
stored by elfread.c in the high bit of the info field. Use this
to decide if the function is standard MIPS. Otherwise if bit 0
of the address is clear, then this is a standard MIPS function. */
- sym = lookup_minimal_symbol_by_pc (memaddr);
+ sym = lookup_minimal_symbol_by_pc (make_compact_addr (memaddr));
if (sym.minsym)
return msymbol_is_mips (sym.minsym);
else
@@ -1150,7 +1194,7 @@ mips_pc_is_mips16 (struct gdbarch *gdbarch, CORE_ADDR memaddr)
elfread.c in the high bit of the info field. Use this to decide
if the function is MIPS16. Otherwise if bit 0 of the address is
set, then ELF file flags will tell if this is a MIPS16 function. */
- sym = lookup_minimal_symbol_by_pc (memaddr);
+ sym = lookup_minimal_symbol_by_pc (make_compact_addr (memaddr));
if (sym.minsym)
return msymbol_is_mips16 (sym.minsym);
else
@@ -1169,7 +1213,7 @@ mips_pc_is_micromips (struct gdbarch *gdbarch, CORE_ADDR memaddr)
if the function is microMIPS. Otherwise if bit 0 of the address
is set, then ELF file flags will tell if this is a microMIPS
function. */
- sym = lookup_minimal_symbol_by_pc (memaddr);
+ sym = lookup_minimal_symbol_by_pc (make_compact_addr (memaddr));
if (sym.minsym)
return msymbol_is_micromips (sym.minsym);
else
@@ -1189,7 +1233,7 @@ mips_pc_isa (struct gdbarch *gdbarch, CORE_ADDR memaddr)
this to decide if the function is MIPS16 or microMIPS or normal
MIPS. Otherwise if bit 0 of the address is set, then ELF file
flags will tell if this is a MIPS16 or a microMIPS function. */
- sym = lookup_minimal_symbol_by_pc (memaddr);
+ sym = lookup_minimal_symbol_by_pc (make_compact_addr (memaddr));
if (sym.minsym)
{
if (msymbol_is_micromips (sym.minsym))
@@ -1210,6 +1254,67 @@ mips_pc_isa (struct gdbarch *gdbarch, CORE_ADDR memaddr)
}
}
+/* Set the ISA bit correctly in the PC, used by DWARF-2 machinery.
+ The need for comes from the ISA bit having been cleared, making
+ addresses in FDE, range records, etc. referring to compressed code
+ different to those in line information, the symbol table and finally
+ the PC register. That in turn confuses many operations. */
+
+static CORE_ADDR
+mips_adjust_dwarf2_addr (CORE_ADDR pc)
+{
+ pc = unmake_compact_addr (pc);
+ return mips_pc_is_mips (pc) ? pc : make_compact_addr (pc);
+}
+
+/* Recalculate the line record requested so that the resulting PC has
+ the ISA bit set correctly, used by DWARF-2 machinery. The need for
+ this adjustment comes from some records associated with compressed
+ code having the ISA bit cleared, most notably at function prologue
+ ends. The ISA bit is in this context retrieved from the minimal
+ symbol covering the address requested, which in turn has been
+ constructed from the binary's symbol table rather than DWARF-2
+ information. The correct setting of the ISA bit is required for
+ breakpoint addresses to correctly match against the stop PC.
+
+ As line entries can specify relative address adjustments we need to
+ keep track of the absolute value of the last line address recorded
+ in line information, so that we can calculate the actual address to
+ apply the ISA bit adjustment to. We use PC for this tracking and
+ keep the original address there.
+
+ As such relative address adjustments can be odd within compressed
+ code we need to keep track of the last line address with the ISA
+ bit adjustment applied too, as the original address may or may not
+ have had the ISA bit set. We use ADJ_PC for this tracking and keep
+ the adjusted address there.
+
+ For relative address adjustments we then use these variables to
+ calculate the address intended by line information, which will be
+ PC-relative, and return an updated adjustment carrying ISA bit
+ information, which will be ADJ_PC-relative. For absolute address
+ adjustments we just return the same address that we store in ADJ_PC
+ too.
+
+ As the first line entry can be relative to an implied address value
+ of 0 we need to have the initial address set up that we store in PC
+ and ADJ_PC. This is arranged with a call from `dwarf_decode_lines_1'
+ that sets PC to 0 and ADJ_PC accordingly, usually 0 as well. */
+
+static CORE_ADDR
+mips_adjust_dwarf2_line (CORE_ADDR addr, int rel)
+{
+ static CORE_ADDR adj_pc;
+ static CORE_ADDR pc;
+ CORE_ADDR isa_pc;
+
+ pc = rel ? pc + addr : addr;
+ isa_pc = mips_adjust_dwarf2_addr (pc);
+ addr = rel ? isa_pc - adj_pc : isa_pc;
+ adj_pc = isa_pc;
+ return addr;
+}
+
/* Various MIPS16 thunk (aka stub or trampoline) names. */
static const char mips_str_mips16_call_stub[] = "__mips16_call_stub_";
@@ -1259,8 +1364,6 @@ mips_read_pc (struct regcache *regcache)
LONGEST pc;
regcache_cooked_read_signed (regcache, regnum, &pc);
- if (is_compact_addr (pc))
- pc = unmake_compact_addr (pc);
return pc;
}
@@ -1270,8 +1373,6 @@ mips_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame)
CORE_ADDR pc;
pc = frame_unwind_register_signed (next_frame, gdbarch_pc_regnum (gdbarch));
- if (is_compact_addr (pc))
- pc = unmake_compact_addr (pc);
/* macro/2012-04-20: This hack skips over MIPS16 call thunks as
intermediate frames. In this case we can get the caller's address
from $ra, or if $ra contains an address within a thunk as well, then
@@ -1281,15 +1382,9 @@ mips_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame)
{
pc = frame_unwind_register_signed
(next_frame, gdbarch_num_regs (gdbarch) + MIPS_RA_REGNUM);
- if (is_compact_addr (pc))
- pc = unmake_compact_addr (pc);
if (mips_in_frame_stub (pc))
- {
- pc = frame_unwind_register_signed
- (next_frame, gdbarch_num_regs (gdbarch) + MIPS_S2_REGNUM);
- if (is_compact_addr (pc))
- pc = unmake_compact_addr (pc);
- }
+ pc = frame_unwind_register_signed
+ (next_frame, gdbarch_num_regs (gdbarch) + MIPS_S2_REGNUM);
}
return pc;
}
@@ -1323,10 +1418,7 @@ mips_write_pc (struct regcache *regcache, CORE_ADDR pc)
{
int regnum = gdbarch_pc_regnum (get_regcache_arch (regcache));
- if (mips_pc_is_mips (pc))
- regcache_cooked_write_unsigned (regcache, regnum, pc);
- else
- regcache_cooked_write_unsigned (regcache, regnum, make_compact_addr (pc));
+ regcache_cooked_write_unsigned (regcache, regnum, pc);
}
/* Fetch and return instruction from the specified location. Handle
@@ -3765,9 +3857,6 @@ mips_addr_bits_remove (struct gdbarch *gdbarch, CORE_ADDR addr)
{
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
- if (is_compact_addr (addr))
- addr = unmake_compact_addr (addr);
-
if (mips_mask_address_p (tdep) && (((ULONGEST) addr) >> 32 == 0xffffffffUL))
/* This hack is a work-around for existing boards using PMON, the
simulator, and any other 64-bit targets that doesn't have true
@@ -4466,25 +4555,9 @@ mips_eabi_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
"mips_eabi_push_dummy_call: %d len=%d type=%d",
argnum + 1, len, (int) typecode);
- /* Function pointer arguments to mips16 code need to be made into
- mips16 pointers. */
- if (typecode == TYPE_CODE_PTR
- && TYPE_CODE (TYPE_TARGET_TYPE (arg_type)) == TYPE_CODE_FUNC)
- {
- CORE_ADDR addr = extract_signed_integer (value_contents (arg),
- len, byte_order);
- if (mips_pc_is_mips (addr))
- val = value_contents (arg);
- else
- {
- store_signed_integer (valbuf, len, byte_order,
- make_compact_addr (addr));
- val = valbuf;
- }
- }
/* The EABI passes structures that do not fit in a register by
reference. */
- else if (len > regsize
+ if (len > regsize
&& (typecode == TYPE_CODE_STRUCT || typecode == TYPE_CODE_UNION))
{
store_unsigned_integer (valbuf, regsize, byte_order,
@@ -5849,7 +5922,6 @@ mips_o64_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
for (argnum = 0; argnum < nargs; argnum++)
{
const gdb_byte *val;
- gdb_byte valbuf[MAX_REGISTER_SIZE];
struct value *arg = args[argnum];
struct type *arg_type = check_typedef (value_type (arg));
int len = TYPE_LENGTH (arg_type);
@@ -5862,21 +5934,6 @@ mips_o64_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
val = value_contents (arg);
- /* Function pointer arguments to mips16 code need to be made into
- mips16 pointers. */
- if (typecode == TYPE_CODE_PTR
- && TYPE_CODE (TYPE_TARGET_TYPE (arg_type)) == TYPE_CODE_FUNC)
- {
- CORE_ADDR addr = extract_signed_integer (value_contents (arg),
- len, byte_order);
- if (!mips_pc_is_mips (addr))
- {
- store_signed_integer (valbuf, len, byte_order,
- make_compact_addr (addr));
- val = valbuf;
- }
- }
-
/* Floating point arguments passed in registers have to be
treated specially. On 32-bit architectures, doubles are
passed in register pairs; the even FP register gets the
@@ -7833,27 +7890,15 @@ mips_skip_trampoline_code (struct frame_info *frame, CORE_ADDR pc)
new_pc = mips_skip_mips16_trampoline_code (frame, pc);
if (new_pc)
- {
- pc = new_pc;
- if (is_compact_addr (pc))
- pc = unmake_compact_addr (pc);
- }
+ pc = new_pc;
new_pc = find_solib_trampoline_target (frame, pc);
if (new_pc)
- {
- pc = new_pc;
- if (is_compact_addr (pc))
- pc = unmake_compact_addr (pc);
- }
+ pc = new_pc;
new_pc = mips_skip_pic_trampoline_code (frame, pc);
if (new_pc)
- {
- pc = new_pc;
- if (is_compact_addr (pc))
- pc = unmake_compact_addr (pc);
- }
+ pc = new_pc;
}
while (pc != target_pc);
@@ -8509,6 +8554,9 @@ mips_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
set_gdbarch_elf_make_msymbol_special (gdbarch,
mips_elf_make_msymbol_special);
+ set_gdbarch_make_symbol_special (gdbarch, mips_make_symbol_special);
+ set_gdbarch_adjust_dwarf2_addr (gdbarch, mips_adjust_dwarf2_addr);
+ set_gdbarch_adjust_dwarf2_line (gdbarch, mips_adjust_dwarf2_line);
regnum = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct mips_regnum);
*regnum = mips_regnum;