[RFA] New GDB target iq2000

Corinna Vinschen
2005-02-22T11:43:15Z

Hi,

this posting contributes the iq2000 code for GDB.

There's just one problem with it. Older GCC code (older than two days,
actually), emits an asymmetrical register numbering in the dwarf2 debugging
output. The iq2000 uses register 31 as link register, which contains the
return address to the calling function. For some reason GCC emitted the
register number 26 in the dwarf2 information for this register. Every
other register has been used unchanged in dwarf2, so there was no
unambiguous translation from dwarf2 register numbers to real register
numbers, if the dwarf2 register was "26". This has been fixed yesterday
in GCC HEAD.

As a result, the dwarf2 frame sniffer has a problem with code generated
by GCC's older than two days. This is no problem for the iq2000 frame
sniffer implemented in iq2000-tdep.c, but as usual, the iq2000 frame
sniffer is appended after the dwarf2 frame sniffer:

frame_unwind_append_sniffer (gdbarch, dwarf2_frame_sniffer);
frame_unwind_append_sniffer (gdbarch, iq2000_frame_sniffer);

Would that be a good reason to disable the dwarf2 frame sniffer for now?
Or shall I leave that as is?

Corinna

ChangeLog:
==========

2005-02-?? Corinna Vinschen <vinschen@redhat.com>

* Makefile.in: Add dependencies for iq2000-tdep.o.
* configure.tgt: Add iq2000-*-* target.
* iq2000-tdep.c: New file.
* config/iq2000/iq2000.mt: New file.

testsuite/ChangeLog:
====================

2005-02-?? Corinna Vinschen <vinschen@redhat.com>

* gdb.asm/asm-source.exp: Add iq2000 case.
* gdb.asm/iq2000.inc: New file.

Index: Makefile.in
===================================================================
RCS file: /cvs/src/src/gdb/Makefile.in,v
retrieving revision 1.699
diff -u -p -r1.699 Makefile.in
--- Makefile.in 16 Feb 2005 13:21:47 -0000 1.699
+++ Makefile.in 21 Feb 2005 20:17:32 -0000
@@ -2115,6 +2115,10 @@ inf-ttrace.o: inf-ttrace.c $(defs_h) $(c
interps.o: interps.c $(defs_h) $(gdbcmd_h) $(ui_out_h) $(event_loop_h) \
$(event_top_h) $(interps_h) $(completer_h) $(gdb_string_h) \
$(gdb_events_h) $(gdb_assert_h) $(top_h) $(exceptions_h)
+iq2000-tdep.o: iq2000-tdep.c $(defs_h) $(frame_h) $(frame_base_h) \
+ $(frame_unwind_h) $(dwarf2_frame_h) $(gdbtypes_h) $(value_h) \
+ $(dis_asm_h) $(gdb_string_h) $(arch_utils_h) $(regcache_h) \
+ $(osabi_h) $(gdbcore_h)
irix5-nat.o: irix5-nat.c $(defs_h) $(inferior_h) $(gdbcore_h) $(target_h) \
$(regcache_h) $(gdb_string_h) $(gregset_h) $(mips_tdep_h)
jv-exp.o: jv-exp.c $(defs_h) $(gdb_string_h) $(expression_h) $(value_h) \
Index: configure.tgt
===================================================================
RCS file: /cvs/src/src/gdb/configure.tgt,v
retrieving revision 1.159
diff -u -p -r1.159 configure.tgt
--- configure.tgt 12 Feb 2005 10:38:50 -0000 1.159
+++ configure.tgt 21 Feb 2005 20:17:33 -0000
@@ -102,6 +102,8 @@ ia64-*-linux*) gdb_target=linux
;;
ia64*-*-*) gdb_target=ia64 ;;

+iq2000-*-*) gdb_target=iq2000 ;;
+
m32r*-*-linux*) gdb_target=linux ;;
m32r*-*-*) gdb_target=m32r ;;

Index: iq2000-tdep.c
===================================================================
RCS file: iq2000-tdep.c
diff -N iq2000-tdep.c
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ iq2000-tdep.c 21 Feb 2005 20:17:33 -0000
@@ -0,0 +1,874 @@
+/* Target-dependent code for the IQ2000 architecture, for GDB, the GNU
+ Debugger.
+
+ Copyright 2000, 2004, 2005 Free Software Foundation, Inc.
+
+ Contributed by Red Hat.
+
+ This file is part of GDB.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+#include "defs.h"
+#include "frame.h"
+#include "frame-base.h"
+#include "frame-unwind.h"
+#include "dwarf2-frame.h"
+#include "gdbtypes.h"
+#include "value.h"
+#include "dis-asm.h"
+#include "gdb_string.h"
+#include "arch-utils.h"
+#include "regcache.h"
+#include "osabi.h"
+#include "gdbcore.h"
+
+enum gdb_regnum
+{
+ E_R0_REGNUM, E_R1_REGNUM, E_R2_REGNUM, E_R3_REGNUM,
+ E_R4_REGNUM, E_R5_REGNUM, E_R6_REGNUM, E_R7_REGNUM,
+ E_R8_REGNUM, E_R9_REGNUM, E_R10_REGNUM, E_R11_REGNUM,
+ E_R12_REGNUM, E_R13_REGNUM, E_R14_REGNUM, E_R15_REGNUM,
+ E_R16_REGNUM, E_R17_REGNUM, E_R18_REGNUM, E_R19_REGNUM,
+ E_R20_REGNUM, E_R21_REGNUM, E_R22_REGNUM, E_R23_REGNUM,
+ E_R24_REGNUM, E_R25_REGNUM, E_R26_REGNUM, E_R27_REGNUM,
+ E_R28_REGNUM, E_R29_REGNUM, E_R30_REGNUM, E_R31_REGNUM,
+ E_PC_REGNUM,
+ E_LR_REGNUM = E_R31_REGNUM, /* Link register. */
+ E_SP_REGNUM = E_R29_REGNUM, /* Stack pointer. */
+ E_FP_REGNUM = E_R27_REGNUM, /* Frame pointer. */
+ E_FN_RETURN_REGNUM = E_R2_REGNUM, /* Function return value register. */
+ E_1ST_ARGREG = E_R4_REGNUM, /* 1st function arg register. */
+ E_LAST_ARGREG = E_R11_REGNUM, /* Last function arg register. */
+ E_NUM_REGS = E_PC_REGNUM + 1
+};
+
+/* Use an invalid address value as 'not available' marker. */
+enum { REG_UNAVAIL = (CORE_ADDR) -1 };
+
+struct iq2000_frame_cache
+{
+ /* Base address. */
+ CORE_ADDR base;
+ CORE_ADDR pc;
+ LONGEST framesize;
+ int using_fp;
+ CORE_ADDR saved_sp;
+ CORE_ADDR saved_regs [E_NUM_REGS];
+};
+
+/* Harvard methods: */
+
+static CORE_ADDR
+insn_ptr_from_addr (CORE_ADDR addr) /* CORE_ADDR to target pointer. */
+{
+ return addr & 0x7fffffffL;
+}
+
+static CORE_ADDR
+insn_addr_from_ptr (CORE_ADDR ptr) /* target_pointer to CORE_ADDR. */
+{
+ return (ptr & 0x7fffffffL) | 0x80000000L;
+}
+
+/* Function: pointer_to_address
+ Convert a target pointer to an address in host (CORE_ADDR) format. */
+
+static CORE_ADDR
+iq2000_pointer_to_address (struct type * type, const void * buf)
+{
+ enum type_code target = TYPE_CODE (TYPE_TARGET_TYPE (type));
+ CORE_ADDR addr = extract_unsigned_integer (buf, TYPE_LENGTH (type));
+
+ if (target == TYPE_CODE_FUNC
+ || target == TYPE_CODE_METHOD
+ || (TYPE_FLAGS (TYPE_TARGET_TYPE (type)) & TYPE_FLAG_CODE_SPACE) != 0)
+ addr = insn_addr_from_ptr (addr);
+
+ return addr;
+}
+
+/* Function: address_to_pointer
+ Convert a host-format address (CORE_ADDR) into a target pointer. */
+
+static void
+iq2000_address_to_pointer (struct type *type, void *buf, CORE_ADDR addr)
+{
+ enum type_code target = TYPE_CODE (TYPE_TARGET_TYPE (type));
+
+ if (target == TYPE_CODE_FUNC || target == TYPE_CODE_METHOD)
+ addr = insn_ptr_from_addr (addr);
+ store_unsigned_integer (buf, TYPE_LENGTH (type), addr);
+}
+
+/* Real register methods: */
+
+/* Function: register_name
+ Returns the name of the iq2000 register number N. */
+
+static const char *
+iq2000_register_name (int regnum)
+{
+ static const char * names[E_NUM_REGS] =
+ {
+ "r0", "r1", "r2", "r3", "r4",
+ "r5", "r6", "r7", "r8", "r9",
+ "r10", "r11", "r12", "r13", "r14",
+ "r15", "r16", "r17", "r18", "r19",
+ "r20", "r21", "r22", "r23", "r24",
+ "r25", "r26", "r27", "r28", "r29",
+ "r30", "r31",
+ "pc"
+ };
+ if (regnum < 0 || regnum >= E_NUM_REGS)
+ return NULL;
+ return names[regnum];
+}
+
+/* Prologue analysis methods: */
+
+/* ADDIU insn (001001 rs(5) rt(5) imm(16)). */
+#define INSN_IS_ADDIU(X) (((X) & 0xfc000000) == 0x24000000)
+#define ADDIU_REG_SRC(X) (((X) & 0x03e00000) >> 21)
+#define ADDIU_REG_TGT(X) (((X) & 0x001f0000) >> 16)
+#define ADDIU_IMMEDIATE(X) ((signed short) ((X) & 0x0000ffff))
+
+/* "MOVE" (OR) insn (000000 rs(5) rt(5) rd(5) 00000 100101). */
+#define INSN_IS_MOVE(X) (((X) & 0xffe007ff) == 0x00000025)
+#define MOVE_REG_SRC(X) (((X) & 0x001f0000) >> 16)
+#define MOVE_REG_TGT(X) (((X) & 0x0000f800) >> 11)
+
+/* STORE WORD insn (101011 rs(5) rt(5) offset(16)). */
+#define INSN_IS_STORE_WORD(X) (((X) & 0xfc000000) == 0xac000000)
+#define SW_REG_INDEX(X) (((X) & 0x03e00000) >> 21)
+#define SW_REG_SRC(X) (((X) & 0x001f0000) >> 16)
+#define SW_OFFSET(X) ((signed short) ((X) & 0x0000ffff))
+
+/* Function: find_last_line_symbol
+
+ Given an address range, first find a line symbol corresponding to
+ the starting address. Then find the last line symbol within the
+ range that has a line number less than or equal to the first line.
+
+ For optimized code with code motion, this finds the last address
+ for the lowest-numbered line within the address range. */
+
+static struct symtab_and_line
+find_last_line_symbol (CORE_ADDR start, CORE_ADDR end, int notcurrent)
+{
+ struct symtab_and_line sal = find_pc_line (start, notcurrent);
+ struct symtab_and_line best_sal = sal;
+
+ if (sal.pc == 0 || sal.line == 0 || sal.end == 0)
+ return sal;
+
+ do
+ {
+ if (sal.line && sal.line <= best_sal.line)
+ best_sal = sal;
+ sal = find_pc_line (sal.end, notcurrent);
+ }
+ while (sal.pc && sal.pc < end);
+
+ return best_sal;
+}
+
+/* Function: scan_prologue
+ Decode the instructions within the given address range.
+ Decide when we must have reached the end of the function prologue.
+ If a frame_info pointer is provided, fill in its prologue information.
+
+ Returns the address of the first instruction after the prologue. */
+
+static CORE_ADDR
+iq2000_scan_prologue (CORE_ADDR scan_start,
+ CORE_ADDR scan_end,
+ struct frame_info *fi,
+ struct iq2000_frame_cache *cache)
+{
+ struct symtab_and_line sal;
+ CORE_ADDR pc;
+ CORE_ADDR loop_end;
+ int found_store_lr = 0;
+ int found_decr_sp = 0;
+ int srcreg;
+ int tgtreg;
+ signed short offset;
+
+ if (scan_end == (CORE_ADDR) 0)
+ {
+ loop_end = scan_start + 100;
+ sal.end = sal.pc = 0;
+ }
+ else
+ {
+ loop_end = scan_end;
+ if (fi)
+ sal = find_last_line_symbol (scan_start, scan_end, 0);
+ }
+
+ /* Saved registers:
+ We first have to save the saved register's offset, and
+ only later do we compute its actual address. Since the
+ offset can be zero, we must first initialize all the
+ saved regs to minus one (so we can later distinguish
+ between one that's not saved, and one that's saved at zero). */
+ for (srcreg = 0; srcreg < E_NUM_REGS; srcreg ++)
+ cache->saved_regs[srcreg] = -1;
+ cache->using_fp = 0;
+ cache->framesize = 0;
+
+ for (pc = scan_start; pc < loop_end; pc += 4)
+ {
+ LONGEST insn = read_memory_unsigned_integer (pc, 4);
+ /* Skip any instructions writing to (sp) or decrementing the
+ SP. */
+ if ((insn & 0xffe00000) == 0xac200000)
+ {
+ /* sw using SP/%1 as base. */
+ /* LEGACY -- from assembly-only port. */
+ tgtreg = ((insn >> 16) & 0x1f);
+ if (tgtreg >= 0 && tgtreg < E_NUM_REGS)
+ cache->saved_regs[tgtreg] = -((signed short) (insn & 0xffff));
+
+ if (tgtreg == E_LR_REGNUM)
+ found_store_lr = 1;
+ continue;
+ }
+
+ if ((insn & 0xffff8000) == 0x20218000)
+ {
+ /* addi %1, %1, -N == addi %sp, %sp, -N */
+ /* LEGACY -- from assembly-only port */
+ found_decr_sp = 1;
+ cache->framesize = -((signed short) (insn & 0xffff));
+ continue;
+ }
+
+ if (INSN_IS_ADDIU (insn))
+ {
+ srcreg = ADDIU_REG_SRC (insn);
+ tgtreg = ADDIU_REG_TGT (insn);
+ offset = ADDIU_IMMEDIATE (insn);
+ if (srcreg == E_SP_REGNUM && tgtreg == E_SP_REGNUM)
+ cache->framesize = -offset;
+ continue;
+ }
+
+ if (INSN_IS_STORE_WORD (insn))
+ {
+ srcreg = SW_REG_SRC (insn);
+ tgtreg = SW_REG_INDEX (insn);
+ offset = SW_OFFSET (insn);
+
+ if (tgtreg == E_SP_REGNUM || tgtreg == E_FP_REGNUM)
+ {
+ /* "push" to stack (via SP or FP reg) */
+ if (cache->saved_regs[srcreg] == -1) /* Don't save twice. */
+ cache->saved_regs[srcreg] = offset;
+ continue;
+ }
+ }
+
+ if (INSN_IS_MOVE (insn))
+ {
+ srcreg = MOVE_REG_SRC (insn);
+ tgtreg = MOVE_REG_TGT (insn);
+
+ if (srcreg == E_SP_REGNUM && tgtreg == E_FP_REGNUM)
+ {
+ /* Copy sp to fp. */
+ cache->using_fp = 1;
+ continue;
+ }
+ }
+
+ /* Unknown instruction encountered in frame. Bail out?
+ 1) If we have a subsequent line symbol, we can keep going.
+ 2) If not, we need to bail out and quit scanning instructions. */
+
+ if (fi && sal.end && (pc < sal.end)) /* Keep scanning. */
+ continue;
+ else /* bail */
+ break;
+ }
+
+ return pc;
+}
+
+static void
+iq2000_init_frame_cache (struct iq2000_frame_cache *cache)
+{
+ int i;
+
+ cache->base = 0;
+ cache->framesize = 0;
+ cache->using_fp = 0;
+ cache->saved_sp = 0;
+ for (i = 0; i < E_NUM_REGS; i++)
+ cache->saved_regs[i] = -1;
+}
+
+/* Function: iq2000_skip_prologue
+ If the input address is in a function prologue,
+ returns the address of the end of the prologue;
+ else returns the input address.
+
+ Note: the input address is likely to be the function start,
+ since this function is mainly used for advancing a breakpoint
+ to the first line, or stepping to the first line when we have
+ stepped into a function call. */
+
+static CORE_ADDR
+iq2000_skip_prologue (CORE_ADDR pc)
+{
+ CORE_ADDR func_addr = 0 , func_end = 0;
+
+ if (find_pc_partial_function (pc, NULL, & func_addr, & func_end))
+ {
+ struct symtab_and_line sal;
+ struct iq2000_frame_cache cache;
+
+ /* Found a function. */
+ sal = find_pc_line (func_addr, 0);
+ if (sal.end && sal.end < func_end)
+ /* Found a line number, use it as end of prologue. */
+ return sal.end;
+
+ /* No useable line symbol. Use prologue parsing method. */
+ iq2000_init_frame_cache (&cache);
+ return iq2000_scan_prologue (func_addr, func_end, NULL, &cache);
+ }
+
+ /* No function symbol -- just return the PC. */
+ return (CORE_ADDR) pc;
+}
+
+static struct iq2000_frame_cache *
+iq2000_frame_cache (struct frame_info *next_frame, void **this_cache)
+{
+ struct iq2000_frame_cache *cache;
+ CORE_ADDR current_pc;
+ int i;
+
+ if (*this_cache)
+ return *this_cache;
+
+ cache = FRAME_OBSTACK_ZALLOC (struct iq2000_frame_cache);
+ iq2000_init_frame_cache (cache);
+ *this_cache = cache;
+
+ cache->base = frame_unwind_register_unsigned (next_frame, E_FP_REGNUM);
+ //if (cache->base == 0)
+ //return cache;
+
+ current_pc = frame_pc_unwind (next_frame);
+ find_pc_partial_function (current_pc, NULL, &cache->pc, NULL);
+ if (cache->pc != 0)
+ iq2000_scan_prologue (cache->pc, current_pc, next_frame, cache);
+ if (!cache->using_fp)
+ cache->base = frame_unwind_register_unsigned (next_frame, E_SP_REGNUM);
+
+ cache->saved_sp = cache->base + cache->framesize;
+
+ for (i = 0; i < E_NUM_REGS; i++)
+ if (cache->saved_regs[i] != -1)
+ cache->saved_regs[i] += cache->base;
+
+ return cache;
+}
+
+static void
+iq2000_frame_prev_register (struct frame_info *next_frame, void **this_cache,
+ int regnum, int *optimizedp,
+ enum lval_type *lvalp, CORE_ADDR *addrp,
+ int *realnump, void *valuep)
+{
+ struct iq2000_frame_cache *cache = iq2000_frame_cache (next_frame, this_cache);
+ if (regnum == E_SP_REGNUM && cache->saved_sp)
+ {
+ *optimizedp = 0;
+ *lvalp = not_lval;
+ *addrp = 0;
+ *realnump = -1;
+ if (valuep)
+ store_unsigned_integer (valuep, 4, cache->saved_sp);
+ return;
+ }
+
+ if (regnum == E_PC_REGNUM)
+ regnum = E_LR_REGNUM;
+
+ if (regnum < E_NUM_REGS && cache->saved_regs[regnum] != -1)
+ {
+ *optimizedp = 0;
+ *lvalp = lval_memory;
+ *addrp = cache->saved_regs[regnum];
+ *realnump = -1;
+ if (valuep)
+ read_memory (*addrp, valuep, register_size (current_gdbarch, regnum));
+ return;
+ }
+
+ *optimizedp = 0;
+ *lvalp = lval_register;
+ *addrp = 0;
+ *realnump = regnum;
+ if (valuep)
+ frame_unwind_register (next_frame, (*realnump), valuep);
+}
+
+static void
+iq2000_frame_this_id (struct frame_info *next_frame, void **this_cache,
+ struct frame_id *this_id)
+{
+ struct iq2000_frame_cache *cache = iq2000_frame_cache (next_frame, this_cache);
+
+ /* This marks the outermost frame. */
+ if (cache->base == 0)
+ return;
+
+ *this_id = frame_id_build (cache->saved_sp, cache->pc);
+}
+
+static const struct frame_unwind iq2000_frame_unwind = {
+ NORMAL_FRAME,
+ iq2000_frame_this_id,
+ iq2000_frame_prev_register
+};
+
+static const struct frame_unwind *
+iq2000_frame_sniffer (struct frame_info *next_frame)
+{
+ return &iq2000_frame_unwind;
+}
+
+static CORE_ADDR
+iq2000_unwind_sp (struct gdbarch *gdbarch, struct frame_info *next_frame)
+{
+ return frame_unwind_register_unsigned (next_frame, E_SP_REGNUM);
+}
+
+static CORE_ADDR
+iq2000_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame)
+{
+ return frame_unwind_register_unsigned (next_frame, E_PC_REGNUM);
+}
+
+static struct frame_id
+iq2000_unwind_dummy_id (struct gdbarch *gdbarch, struct frame_info *next_frame)
+{
+ return frame_id_build (iq2000_unwind_sp (gdbarch, next_frame),
+ frame_pc_unwind (next_frame));
+}
+
+static CORE_ADDR
+iq2000_frame_base_address (struct frame_info *next_frame, void **this_cache)
+{
+ struct iq2000_frame_cache *cache = iq2000_frame_cache (next_frame, this_cache);
+
+ return cache->base;
+}
+
+static const struct frame_base iq2000_frame_base = {
+ &iq2000_frame_unwind,
+ iq2000_frame_base_address,
+ iq2000_frame_base_address,
+ iq2000_frame_base_address
+};
+
+static const unsigned char *
+iq2000_breakpoint_from_pc (CORE_ADDR *pcptr, int *lenptr)
+{
+ static const unsigned char big_breakpoint[] = { 0x00, 0x00, 0x00, 0x0d };
+ static const unsigned char little_breakpoint[] = { 0x0d, 0x00, 0x00, 0x00 };
+
+ if ((*pcptr & 3) != 0)
+ error ("breakpoint_from_pc: invalid breakpoint address 0x%lx",
+ (long) *pcptr);
+
+ *lenptr = 4;
+ return (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG) ? big_breakpoint
+ : little_breakpoint;
+}
+
+/* Target function return value methods: */
+
+/* Function: store_return_value
+ Copy the function return value from VALBUF into the
+ proper location for a function return. */
+
+static void
+iq2000_store_return_value (struct type *type, struct regcache *regcache,
+ const void *valbuf)
+{
+ int len = TYPE_LENGTH (type);
+ int regno = E_FN_RETURN_REGNUM;
+
+ while (len > 0)
+ {
+ char buf[4];
+ int size = len % 4 ?: 4;
+
+ memset (buf, 0, 4);
+ memcpy (buf + 4 - size, valbuf, size);
+ regcache_raw_write (regcache, regno++, buf);
+ len -= size;
+ valbuf = ((char *) valbuf) + size;
+ }
+}
+
+/* Function: use_struct_convention
+ Returns non-zero if the given struct type will be returned using
+ a special convention, rather than the normal function return method. */
+
+static int
+iq2000_use_struct_convention (struct type *type)
+{
+ return ((TYPE_CODE (type) == TYPE_CODE_STRUCT)
+ || (TYPE_CODE (type) == TYPE_CODE_UNION))
+ && TYPE_LENGTH (type) > 8;
+}
+
+/* Function: extract_return_value
+ Copy the function's return value into VALBUF.
+ This function is called only in the context of "target function calls",
+ ie. when the debugger forces a function to be called in the child, and
+ when the debugger forces a function to return prematurely via the
+ "return" command. */
+
+static void
+iq2000_extract_return_value (struct type *type, struct regcache *regcache,
+ void *valbuf)
+{
+ /* If the function's return value is 8 bytes or less, it is
+ returned in a register, and if larger than 8 bytes, it is
+ returned in a stack location which is pointed to by the same
+ register. */
+ CORE_ADDR return_buffer;
+ int len = TYPE_LENGTH (type);
+
+ if (len <= (2 * 4))
+ {
+ int regno = E_FN_RETURN_REGNUM;
+
+ /* Return values of <= 8 bytes are returned in
+ FN_RETURN_REGNUM. */
+ while (len > 0)
+ {
+ ULONGEST tmp;
+ int size = len % 4 ?: 4;
+
+ /* By using store_unsigned_integer we avoid having to
+ do anything special for small big-endian values. */
+ regcache_cooked_read_unsigned (regcache, regno++, &tmp);
+ store_unsigned_integer (valbuf, size, tmp);
+ len -= size;
+ valbuf = ((char *) valbuf) + size;
+ }
+ }
+ else
+ {
+ /* Return values > 8 bytes are returned in memory,
+ pointed to by FN_RETURN_REGNUM. */
+ regcache_cooked_read (regcache, E_FN_RETURN_REGNUM, & return_buffer);
+ read_memory (return_buffer, valbuf, TYPE_LENGTH (type));
+ }
+}
+
+static enum return_value_convention
+iq2000_return_value (struct gdbarch *gdbarch, struct type *type,
+ struct regcache *regcache,
+ void *readbuf, const void *writebuf)
+{
+ if (iq2000_use_struct_convention (type))
+ return RETURN_VALUE_STRUCT_CONVENTION;
+ if (writebuf)
+ iq2000_store_return_value (type, regcache, writebuf);
+ else if (readbuf)
+ iq2000_extract_return_value (type, regcache, readbuf);
+ return RETURN_VALUE_REGISTER_CONVENTION;
+}
+
+/* Function: register_virtual_type
+ Returns the default type for register N. */
+
+static struct type *
+iq2000_register_type (struct gdbarch *gdbarch, int regnum)
+{
+ return builtin_type_int32;
+}
+
+static CORE_ADDR
+iq2000_frame_align (struct gdbarch *ignore, CORE_ADDR sp)
+{
+ /* This is the same frame alignment used by gcc. */
+ return ((sp + 7) & ~7);
+}
+
+/* Convenience function to check 8-byte types for being a scalar type
+ or a struct with only one long long or double member. */
+static int
+iq2000_pass_8bytetype_by_address (struct type *type)
+{
+ struct type *ftype;
+
+ /* Skip typedefs. */
+ while (TYPE_CODE (type) == TYPE_CODE_TYPEDEF)
+ type = TYPE_TARGET_TYPE (type);
+ /* Non-struct and non-union types are always passed by value. */
+ if (TYPE_CODE (type) != TYPE_CODE_STRUCT
+ && TYPE_CODE (type) != TYPE_CODE_UNION)
+ return 0;
+ /* Structs with more than 1 field are always passed by address. */
+ if (TYPE_NFIELDS (type) != 1)
+ return 1;
+ /* Get field type. */
+ ftype = (TYPE_FIELDS (type))[0].type;
+ /* The field type must have size 8, otherwise pass by address. */
+ if (TYPE_LENGTH (ftype) != 8)
+ return 1;
+ /* Skip typedefs of field type. */
+ while (TYPE_CODE (ftype) == TYPE_CODE_TYPEDEF)
+ ftype = TYPE_TARGET_TYPE (ftype);
+ /* If field is int or float, pass by value. */
+ if (TYPE_CODE (ftype) == TYPE_CODE_FLT
+ || TYPE_CODE (ftype) == TYPE_CODE_INT)
+ return 0;
+ /* Everything else, pass by address. */
+ return 1;
+}
+
+static CORE_ADDR
+iq2000_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
+ struct regcache *regcache, CORE_ADDR bp_addr,
+ int nargs, struct value **args, CORE_ADDR sp,
+ int struct_return, CORE_ADDR struct_addr)
+{
+ const bfd_byte *val;
+ bfd_byte buf[4];
+ struct type *type;
+ int i, argreg, typelen, slacklen;
+ int stackspace = 0;
+ /* Used to copy struct arguments into the stack. */
+ CORE_ADDR struct_ptr;
+
+ /* First determine how much stack space we will need. */
+ for (i = 0, argreg = E_1ST_ARGREG + (struct_return != 0); i < nargs; i++)
+ {
+ type = value_type (args[i]);
+ typelen = TYPE_LENGTH (type);
+ if (typelen <= 4)
+ {
+ /* Scalars of up to 4 bytes,
+ structs of up to 4 bytes, and
+ pointers. */
+ if (argreg <= E_LAST_ARGREG)
+ argreg++;
+ else
+ stackspace += 4;
+ }
+ else if (typelen == 8 && !iq2000_pass_8bytetype_by_address (type))
+ {
+ /* long long,
+ double, and possibly
+ structs with a single field of long long or double. */
+ if (argreg <= E_LAST_ARGREG - 1)
+ {
+ /* 8-byte arg goes into a register pair
+ (must start with an even-numbered reg) */
+ if (((argreg - E_1ST_ARGREG) % 2) != 0)
+ argreg ++;
+ argreg += 2;
+ }
+ else
+ {
+ argreg = E_LAST_ARGREG + 1; /* no more argregs. */
+ /* 8-byte arg goes on stack, must be 8-byte aligned. */
+ stackspace = ((stackspace + 7) & ~7);
+ stackspace += 8;
+ }
+ }
+ else
+ {
+ /* Structs are passed as pointer to a copy of the struct.
+ So we need room on the stack for a copy of the struct
+ plus for the argument pointer. */
+ if (argreg <= E_LAST_ARGREG)
+ argreg++;
+ else
+ stackspace += 4;
+ /* Care for 8-byte alignment of structs saved on stack. */
+ stackspace += ((typelen + 7) & ~7);
+ }
+ }
+
+ /* Now copy params, in ascending order, into their assigned location
+ (either in a register or on the stack). */
+
+ sp -= (sp % 8); /* align */
+ struct_ptr = sp;
+ sp -= stackspace;
+ sp -= (sp % 8); /* align again */
+ stackspace = 0;
+
+ argreg = E_1ST_ARGREG;
+ if (struct_return)
+ {
+ /* A function that returns a struct will consume one argreg to do so.
+ */
+ regcache_cooked_write_unsigned (regcache, argreg++, struct_addr);
+ }
+
+ for (i = 0; i < nargs; i++)
+ {
+ type = value_type (args[i]);
+ typelen = TYPE_LENGTH (type);
+ val = value_contents (args[i]);
+ if (typelen <= 4)
+ {
+ /* Char, short, int, float, pointer, and structs <= four bytes. */
+ slacklen = (4 - (typelen % 4)) % 4;
+ memset (buf, 0, sizeof (buf));
+ memcpy (buf + slacklen, val, typelen);
+ if (argreg <= E_LAST_ARGREG)
+ {
+ /* Passed in a register. */
+ regcache_raw_write (regcache, argreg++, buf);
+ }
+ else
+ {
+ /* Passed on the stack. */
+ write_memory (sp + stackspace, buf, 4);
+ stackspace += 4;
+ }
+ }
+ else if (typelen == 8 && !iq2000_pass_8bytetype_by_address (type))
+ {
+ /* (long long), (double), or struct consisting of
+ a single (long long) or (double). */
+ if (argreg <= E_LAST_ARGREG - 1)
+ {
+ /* 8-byte arg goes into a register pair
+ (must start with an even-numbered reg) */
+ if (((argreg - E_1ST_ARGREG) % 2) != 0)
+ argreg++;
+ regcache_raw_write (regcache, argreg++, val);
+ regcache_raw_write (regcache, argreg++, val + 4);
+ }
+ else
+ {
+ /* 8-byte arg goes on stack, must be 8-byte aligned. */
+ argreg = E_LAST_ARGREG + 1; /* no more argregs. */
+ stackspace = ((stackspace + 7) & ~7);
+ write_memory (sp + stackspace, val, typelen);
+ stackspace += 8;
+ }
+ }
+ else
+ {
+ /* Store struct beginning at the upper end of the previously
+ computed stack space. Then store the address of the struct
+ using the usual rules for a 4 byte value. */
+ struct_ptr -= ((typelen + 7) & ~7);
+ write_memory (struct_ptr, val, typelen);
+ if (argreg <= E_LAST_ARGREG)
+ regcache_cooked_write_unsigned (regcache, argreg++, struct_ptr);
+ else
+ {
+ store_unsigned_integer (buf, 4, struct_ptr);
+ write_memory (sp + stackspace, buf, 4);
+ stackspace += 4;
+ }
+ }
+ }
+
+ /* Store return address. */
+ regcache_cooked_write_unsigned (regcache, E_LR_REGNUM, bp_addr);
+
+ /* Update stack pointer. */
+ regcache_cooked_write_unsigned (regcache, E_SP_REGNUM, sp);
+
+ /* And that should do it. Return the new stack pointer. */
+ return sp;
+}
+
+/* Function: gdbarch_init
+ Initializer function for the iq2000 gdbarch vector.
+ Called by gdbarch. Sets up the gdbarch vector(s) for this target. */
+
+static struct gdbarch *
+iq2000_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
+{
+ struct gdbarch *gdbarch;
+
+ /* Look up list for candidates - only one. */
+ arches = gdbarch_list_lookup_by_info (arches, &info);
+ if (arches != NULL)
+ return arches->gdbarch;
+
+ gdbarch = gdbarch_alloc (&info, NULL);
+
+ set_gdbarch_num_regs (gdbarch, E_NUM_REGS);
+ set_gdbarch_num_pseudo_regs (gdbarch, 0);
+ set_gdbarch_sp_regnum (gdbarch, E_SP_REGNUM);
+ set_gdbarch_pc_regnum (gdbarch, E_PC_REGNUM);
+ set_gdbarch_register_name (gdbarch, iq2000_register_name);
+ set_gdbarch_address_to_pointer (gdbarch, iq2000_address_to_pointer);
+ set_gdbarch_pointer_to_address (gdbarch, iq2000_pointer_to_address);
+ set_gdbarch_ptr_bit (gdbarch, 4 * TARGET_CHAR_BIT);
+ set_gdbarch_short_bit (gdbarch, 2 * TARGET_CHAR_BIT);
+ set_gdbarch_int_bit (gdbarch, 4 * TARGET_CHAR_BIT);
+ set_gdbarch_long_bit (gdbarch, 4 * TARGET_CHAR_BIT);
+ set_gdbarch_long_long_bit (gdbarch, 8 * TARGET_CHAR_BIT);
+ set_gdbarch_float_bit (gdbarch, 4 * TARGET_CHAR_BIT);
+ set_gdbarch_double_bit (gdbarch, 8 * TARGET_CHAR_BIT);
+ set_gdbarch_long_double_bit (gdbarch, 8 * TARGET_CHAR_BIT);
+ set_gdbarch_float_format (gdbarch, & floatformat_ieee_single_big);
+ set_gdbarch_double_format (gdbarch, & floatformat_ieee_double_big);
+ set_gdbarch_long_double_format (gdbarch, & floatformat_ieee_double_big);
+ set_gdbarch_return_value (gdbarch, iq2000_return_value);
+ set_gdbarch_breakpoint_from_pc (gdbarch, iq2000_breakpoint_from_pc);
+ set_gdbarch_frame_args_skip (gdbarch, 0);
+ set_gdbarch_skip_prologue (gdbarch, iq2000_skip_prologue);
+ set_gdbarch_decr_pc_after_break (gdbarch, 0);
+ set_gdbarch_inner_than (gdbarch, core_addr_lessthan);
+ set_gdbarch_print_insn (gdbarch, print_insn_iq2000);
+ set_gdbarch_register_type (gdbarch, iq2000_register_type);
+ set_gdbarch_frame_align (gdbarch, iq2000_frame_align);
+ set_gdbarch_unwind_sp (gdbarch, iq2000_unwind_sp);
+ set_gdbarch_unwind_pc (gdbarch, iq2000_unwind_pc);
+ set_gdbarch_unwind_dummy_id (gdbarch, iq2000_unwind_dummy_id);
+ frame_base_set_default (gdbarch, &iq2000_frame_base);
+ set_gdbarch_push_dummy_call (gdbarch, iq2000_push_dummy_call);
+
+ gdbarch_init_osabi (info, gdbarch);
+
+ frame_unwind_append_sniffer (gdbarch, dwarf2_frame_sniffer);
+ frame_unwind_append_sniffer (gdbarch, iq2000_frame_sniffer);
+
+ return gdbarch;
+}
+
+/* Function: _initialize_iq2000_tdep
+ Initializer function for the iq2000 module.
+ Called by gdb at start-up. */
+
+void
+_initialize_iq2000_tdep (void)
+{
+ register_gdbarch_init (bfd_arch_iq2000, iq2000_gdbarch_init);
+}
Index: config/iq2000/iq2000.mt
===================================================================
RCS file: config/iq2000/iq2000.mt
diff -N config/iq2000/iq2000.mt
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ config/iq2000/iq2000.mt 21 Feb 2005 20:17:33 -0000
@@ -0,0 +1,3 @@
+TDEPFILES= iq2000-tdep.o
+SIM_OBS= remote-sim.o
+SIM= ../sim/iq2000/libsim.a
Index: testsuite/gdb.asm/asm-source.exp
===================================================================
RCS file: /cvs/src/src/gdb/testsuite/gdb.asm/asm-source.exp,v
retrieving revision 1.54
diff -u -p -r1.54 asm-source.exp
--- testsuite/gdb.asm/asm-source.exp 30 Oct 2004 21:49:30 -0000 1.54
+++ testsuite/gdb.asm/asm-source.exp 21 Feb 2005 20:17:33 -0000
@@ -122,6 +122,9 @@ switch -glob -- [istarget] {
set asm-flags "-I${srcdir}/${subdir} -I${objdir}/${subdir}"
set debug-flags "-gdwarf-2"
}
+ "iq2000-*-*" {
+ set asm-arch iq2000
+ }
"hppa*-linux-*" {
set asm-arch pa
set asm-flags "-I${srcdir}/${subdir} -I${objdir}/${subdir}"
Index: testsuite/gdb.asm/iq2000.inc
===================================================================
RCS file: testsuite/gdb.asm/iq2000.inc
diff -N testsuite/gdb.asm/iq2000.inc
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ testsuite/gdb.asm/iq2000.inc 21 Feb 2005 20:17:33 -0000
@@ -0,0 +1,41 @@
+ comment "subroutine prologue"
+ .macro gdbasm_enter
+ addiu %29, %29, 0xfffc
+ sw %31,0(%29)
+ .endm
+
+ comment "subroutine epilogue"
+ .macro gdbasm_leave
+ lw %31,0(%29)
+ addiu %29, %29, 4
+ jr %31
+ nop
+ .endm
+
+ .macro gdbasm_call subr
+ jal \subr
+ nop
+ .endm
+
+ .macro gdbasm_several_nops
+ nop
+ nop
+ nop
+ nop
+ .endm
+
+ comment "exit (0)"
+ .macro gdbasm_exit0
+ ori %4, %0, 1 # SYS_exit
+ ori %5, %0, 0 # normal exit code
+ ori %6, %0, 0
+ ori %7, %0, 0
+ syscall
+ .endm
+
+ comment "crt0 startup"
+ .macro gdbasm_startup
+ andi %0, %0, 0
+ addiu %29, %0, 0xffc
+ .endm
+

--
Corinna Vinschen
Cygwin Project Co-Leader
Red Hat, Inc.