From d560a54bf578015d03a78407e08d4d7773c4941f Mon Sep 17 00:00:00 2001 From: Alexandre Oliva Date: Tue, 8 Jun 2004 05:29:10 +0000 Subject: [PATCH] * mn10300-tdep.c (mn10300_extract_return_value): Rewrite. (mn10300_store_return_value): Rewrite. (mn10300_type_align): New. (mn10300_use_struct_convention): Rewrite. (mn10300_return_value): New, using all of the above. (mn10300_pop_frame_regular): Add saved_regs_size. (mn10300_gdbarch_init): Remove deprecated rewritten entry points. --- gdb/ChangeLog | 10 +++ gdb/mn10300-tdep.c | 170 ++++++++++++++++++++++++++++++++++++++++----- 2 files changed, 163 insertions(+), 17 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 60f3854930..d5d80d7ae9 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,13 @@ +2004-06-08 Alexandre Oliva + + * mn10300-tdep.c (mn10300_extract_return_value): Rewrite. + (mn10300_store_return_value): Rewrite. + (mn10300_type_align): New. + (mn10300_use_struct_convention): Rewrite. + (mn10300_return_value): New, using all of the above. + (mn10300_pop_frame_regular): Add saved_regs_size. + (mn10300_gdbarch_init): Remove deprecated rewritten entry points. + 2004-06-08 Alexandre Oliva * mn10300-tdep.c (mn10300_analyze_prologue): Don't compute saved diff --git a/gdb/mn10300-tdep.c b/gdb/mn10300-tdep.c index 1ecf8cb80a..dba52e283a 100644 --- a/gdb/mn10300-tdep.c +++ b/gdb/mn10300-tdep.c @@ -122,23 +122,63 @@ mn10300_saved_pc_after_call (struct frame_info *fi) } static void -mn10300_extract_return_value (struct type *type, char *regbuf, char *valbuf) +mn10300_extract_return_value (struct gdbarch *gdbarch, struct type *type, + struct regcache *regcache, void *valbuf) { + char buf[MAX_REGISTER_SIZE]; + int len = TYPE_LENGTH (type); + int reg, regsz; + if (TYPE_CODE (type) == TYPE_CODE_PTR) - memcpy (valbuf, regbuf + DEPRECATED_REGISTER_BYTE (4), TYPE_LENGTH (type)); + reg = 4; else - memcpy (valbuf, regbuf + DEPRECATED_REGISTER_BYTE (0), TYPE_LENGTH (type)); + reg = 0; + + regsz = register_size (gdbarch, reg); + if (len <= regsz) + { + regcache_raw_read (regcache, reg, buf); + memcpy (valbuf, buf, len); + } + else if (len <= 2 * regsz) + { + regcache_raw_read (regcache, reg, buf); + memcpy (valbuf, buf, regsz); + gdb_assert (regsz == register_size (gdbarch, reg + 1)); + regcache_raw_read (regcache, reg + 1, buf); + memcpy ((char *) valbuf + regsz, buf, len - regsz); + } + else + internal_error (__FILE__, __LINE__, + "Cannot extract return value %d bytes long.", len); } static void -mn10300_store_return_value (struct type *type, char *valbuf) +mn10300_store_return_value (struct gdbarch *gdbarch, struct type *type, + struct regcache *regcache, const void *valbuf) { + int len = TYPE_LENGTH (type); + int reg, regsz; + if (TYPE_CODE (type) == TYPE_CODE_PTR) - deprecated_write_register_bytes (DEPRECATED_REGISTER_BYTE (4), valbuf, - TYPE_LENGTH (type)); + reg = 4; else - deprecated_write_register_bytes (DEPRECATED_REGISTER_BYTE (0), valbuf, - TYPE_LENGTH (type)); + reg = 0; + + regsz = register_size (gdbarch, reg); + + if (len <= regsz) + regcache_raw_write_part (regcache, reg, 0, len, valbuf); + else if (len <= 2 * regsz) + { + regcache_raw_write (regcache, reg, valbuf); + gdb_assert (regsz == register_size (gdbarch, reg + 1)); + regcache_raw_write_part (regcache, reg+1, 0, + len - regsz, (char *) valbuf + regsz); + } + else + internal_error (__FILE__, __LINE__, + "Cannot store return value %d bytes long.", len); } static struct frame_info *analyze_dummy_frame (CORE_ADDR, CORE_ADDR); @@ -164,12 +204,111 @@ analyze_dummy_frame (CORE_ADDR pc, CORE_ADDR frame) #define MY_FRAME_IN_FP 0x2 #define NO_MORE_FRAMES 0x4 +/* Compute the alignment required by a type. */ + +static int +mn10300_type_align (struct type *type) +{ + int i, align = 1; + + switch (TYPE_CODE (type)) + { + case TYPE_CODE_INT: + case TYPE_CODE_ENUM: + case TYPE_CODE_SET: + case TYPE_CODE_RANGE: + case TYPE_CODE_CHAR: + case TYPE_CODE_BOOL: + case TYPE_CODE_FLT: + case TYPE_CODE_PTR: + case TYPE_CODE_REF: + return TYPE_LENGTH (type); + + case TYPE_CODE_COMPLEX: + return TYPE_LENGTH (type) / 2; + + case TYPE_CODE_STRUCT: + case TYPE_CODE_UNION: + for (i = 0; i < TYPE_NFIELDS (type); i++) + { + int falign = mn10300_type_align (TYPE_FIELD_TYPE (type, i)); + while (align < falign) + align <<= 1; + } + return align; + + case TYPE_CODE_ARRAY: + /* HACK! Structures containing arrays, even small ones, are not + elligible for returning in registers. */ + return 256; + + case TYPE_CODE_TYPEDEF: + return mn10300_type_align (check_typedef (type)); + + default: + abort (); + } +} /* Should call_function allocate stack space for a struct return? */ static int -mn10300_use_struct_convention (int gcc_p, struct type *type) +mn10300_use_struct_convention (struct type *type) { - return (TYPE_NFIELDS (type) > 1 || TYPE_LENGTH (type) > 8); + /* Structures bigger than a pair of words can't be returned in + registers. */ + if (TYPE_LENGTH (type) > 8) + return 1; + + switch (TYPE_CODE (type)) + { + case TYPE_CODE_STRUCT: + case TYPE_CODE_UNION: + /* Structures with a single field are handled as the field + itself. */ + if (TYPE_NFIELDS (type) == 1) + return mn10300_use_struct_convention (TYPE_FIELD_TYPE (type, 0)); + + /* Structures with word or double-word size are passed in memory, as + long as they require at least word alignment. */ + if (mn10300_type_align (type) >= 4) + return 0; + + return 1; + + /* Arrays are addressable, so they're never returned in + registers. This condition can only hold when the array is + the only field of a struct or union. */ + case TYPE_CODE_ARRAY: + return 1; + + case TYPE_CODE_TYPEDEF: + return mn10300_use_struct_convention (check_typedef (type)); + + default: + return 0; + } +} + +/* Determine, for architecture GDBARCH, how a return value of TYPE + should be returned. If it is supposed to be returned in registers, + and READBUF is non-zero, read the appropriate value from REGCACHE, + and copy it into READBUF. If WRITEBUF is non-zero, write the value + from WRITEBUF into REGCACHE. */ + +static enum return_value_convention +mn10300_return_value (struct gdbarch *gdbarch, struct type *type, + struct regcache *regcache, void *readbuf, + const void *writebuf) +{ + if (mn10300_use_struct_convention (type)) + return RETURN_VALUE_STRUCT_CONVENTION; + + if (readbuf) + mn10300_extract_return_value (gdbarch, type, regcache, readbuf); + if (writebuf) + mn10300_store_return_value (gdbarch, type, regcache, writebuf); + + return RETURN_VALUE_REGISTER_CONVENTION; } /* The breakpoint instruction must be the same size as the smallest @@ -737,10 +876,9 @@ mn10300_pop_frame_regular (struct frame_info *frame) write_register (regnum, value); } - /* Actually cut back the stack. */ - write_register (SP_REGNUM, get_frame_base (frame)); - - /* Don't we need to set the PC?!? XXX FIXME. */ + /* Actually cut back the stack, adjusted by the saved registers like + ret would. */ + write_register (SP_REGNUM, get_frame_base (frame) + saved_regs_size (frame)); } /* Function: pop_frame @@ -1176,8 +1314,7 @@ mn10300_gdbarch_init (struct gdbarch_info info, set_gdbarch_deprecated_frame_init_saved_regs (gdbarch, mn10300_frame_init_saved_regs); set_gdbarch_deprecated_frame_chain (gdbarch, mn10300_frame_chain); set_gdbarch_deprecated_frame_saved_pc (gdbarch, mn10300_frame_saved_pc); - set_gdbarch_deprecated_extract_return_value (gdbarch, mn10300_extract_return_value); - set_gdbarch_deprecated_store_return_value (gdbarch, mn10300_store_return_value); + set_gdbarch_return_value (gdbarch, mn10300_return_value); set_gdbarch_deprecated_store_struct_return (gdbarch, mn10300_store_struct_return); set_gdbarch_deprecated_pop_frame (gdbarch, mn10300_pop_frame); set_gdbarch_skip_prologue (gdbarch, mn10300_skip_prologue); @@ -1189,7 +1326,6 @@ mn10300_gdbarch_init (struct gdbarch_info info, set_gdbarch_deprecated_reg_struct_has_addr (gdbarch, mn10300_reg_struct_has_addr); set_gdbarch_deprecated_push_return_address (gdbarch, mn10300_push_return_address); - set_gdbarch_use_struct_convention (gdbarch, mn10300_use_struct_convention); tdep->am33_mode = am33_mode;