587 lines
21 KiB
C
587 lines
21 KiB
C
/* Parameters for target execution on an RS6000, for GDB, the GNU debugger.
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Copyright 1986, 1987, 1989, 1991, 1992, 1993, 1994
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Free Software Foundation, Inc.
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Contributed by IBM Corporation.
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
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/* Minimum possible text address in AIX */
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#define TEXT_SEGMENT_BASE 0x10000000
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/* Load segment of a given pc value. */
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#define PC_LOAD_SEGMENT(PC) pc_load_segment_name(PC)
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/* AIX cc seems to get this right. */
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#define BELIEVE_PCC_PROMOTION 1
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/* return true if a given `pc' value is in `call dummy' function. */
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/* FIXME: This just checks for the end of the stack, which is broken
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for things like stepping through gcc nested function stubs. */
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#define PC_IN_CALL_DUMMY(STOP_PC, STOP_SP, STOP_FRAME_ADDR) \
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(STOP_SP < STOP_PC && STOP_PC < STACK_END_ADDR)
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#if 0
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extern unsigned int text_start, data_start;
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extern char *corefile;
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#endif
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extern int inferior_pid;
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/* setpgrp() messes up controling terminal. The other version of it
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requires libbsd.a. */
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#define setpgrp(XX,YY) setpgid (XX, YY)
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/* We are missing register descriptions in the system header files. Sigh! */
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struct regs {
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int gregs [32]; /* general purpose registers */
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int pc; /* program conter */
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int ps; /* processor status, or machine state */
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};
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struct fp_status {
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double fpregs [32]; /* floating GP registers */
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};
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/* To be used by function_frame_info. */
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struct aix_framedata {
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int offset; /* # of bytes in gpr's and fpr's are saved */
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int saved_gpr; /* smallest # of saved gpr */
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int saved_fpr; /* smallest # of saved fpr */
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int alloca_reg; /* alloca register number (frame ptr) */
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char frameless; /* true if frameless functions. */
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char nosavedpc; /* true if pc not saved. */
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};
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void
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function_frame_info PARAMS ((CORE_ADDR, struct aix_framedata *));
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/* Define the byte order of the machine. */
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#define TARGET_BYTE_ORDER BIG_ENDIAN
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/* AIX's assembler doesn't grok dollar signs in identifiers.
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So we use dots instead. This item must be coordinated with G++. */
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#undef CPLUS_MARKER
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#define CPLUS_MARKER '.'
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/* Offset from address of function to start of its code.
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Zero on most machines. */
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#define FUNCTION_START_OFFSET 0
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/* Advance PC across any function entry prologue instructions
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to reach some "real" code. */
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#define SKIP_PROLOGUE(pc) pc = skip_prologue (pc)
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/* If PC is in some function-call trampoline code, return the PC
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where the function itself actually starts. If not, return NULL. */
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#define SKIP_TRAMPOLINE_CODE(pc) skip_trampoline_code (pc)
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/* When a child process is just starting, we sneak in and relocate
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the symbol table (and other stuff) after the dynamic linker has
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figured out where they go. */
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#define SOLIB_CREATE_INFERIOR_HOOK(PID) \
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do { \
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xcoff_relocate_symtab (PID); \
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} while (0)
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/* Number of trap signals we need to skip over, once the inferior process
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starts running. */
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#define START_INFERIOR_TRAPS_EXPECTED 2
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/* AIX has a couple of strange returns from wait(). */
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#define CHILD_SPECIAL_WAITSTATUS(ourstatus, hoststatus) ( \
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/* "stop after load" status. */ \
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(hoststatus) == 0x57c ? (ourstatus)->kind = TARGET_WAITKIND_LOADED, 1 : \
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\
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/* signal 0. I have no idea why wait(2) returns with this status word. */ \
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/* It looks harmless. */ \
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(hoststatus) == 0x7f ? (ourstatus)->kind = TARGET_WAITKIND_SPURIOUS, 1 : \
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\
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/* A normal waitstatus. Let the usual macros deal with it. */ \
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0)
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/* In xcoff, we cannot process line numbers when we see them. This is
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mainly because we don't know the boundaries of the include files. So,
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we postpone that, and then enter and sort(?) the whole line table at
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once, when we are closing the current symbol table in end_symtab(). */
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#define PROCESS_LINENUMBER_HOOK() aix_process_linenos ()
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/* When a target process or core-file has been attached, we sneak in
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and figure out where the shared libraries have got to. */
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#define SOLIB_ADD(a, b, c) \
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if (inferior_pid) \
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/* Attach to process. */ \
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xcoff_relocate_symtab (inferior_pid); \
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else \
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/* Core file. */ \
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xcoff_relocate_core ();
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extern void xcoff_relocate_core PARAMS ((void));
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/* Immediately after a function call, return the saved pc.
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Can't go through the frames for this because on some machines
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the new frame is not set up until the new function executes
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some instructions. */
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#define SAVED_PC_AFTER_CALL(frame) read_register (LR_REGNUM)
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/* Address of end of stack space. */
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#define STACK_END_ADDR 0x2ff80000
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/* Stack grows downward. */
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#define INNER_THAN <
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#if 0
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/* No, we shouldn't use this. push_arguments() should leave stack in a
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proper alignment! */
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/* Stack has strict alignment. */
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#define STACK_ALIGN(ADDR) (((ADDR)+7)&-8)
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#endif
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/* This is how argumets pushed onto stack or passed in registers. */
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#define PUSH_ARGUMENTS(nargs, args, sp, struct_return, struct_addr) \
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sp = push_arguments(nargs, args, sp, struct_return, struct_addr)
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/* Sequence of bytes for breakpoint instruction. */
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#define BREAKPOINT {0x7d, 0x82, 0x10, 0x08}
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/* Amount PC must be decremented by after a breakpoint.
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This is often the number of bytes in BREAKPOINT
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but not always. */
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#define DECR_PC_AFTER_BREAK 0
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/* Nonzero if instruction at PC is a return instruction. */
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/* Allow any of the return instructions, including a trapv and a return
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from interrupt. */
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#define ABOUT_TO_RETURN(pc) \
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((read_memory_integer (pc, 4) & 0xfe8007ff) == 0x4e800020)
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/* Return 1 if P points to an invalid floating point value. */
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#define INVALID_FLOAT(p, len) 0 /* Just a first guess; not checked */
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/* Say how long (ordinary) registers are. This is a piece of bogosity
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used in push_word and a few other places; REGISTER_RAW_SIZE is the
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real way to know how big a register is. */
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#define REGISTER_SIZE 4
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/* Number of machine registers */
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#define NUM_REGS 71
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/* Initializer for an array of names of registers.
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There should be NUM_REGS strings in this initializer. */
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#define REGISTER_NAMES \
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{"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", \
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"r8", "r9", "r10","r11","r12","r13","r14","r15", \
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"r16","r17","r18","r19","r20","r21","r22","r23", \
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"r24","r25","r26","r27","r28","r29","r30","r31", \
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"f0", "f1", "f2", "f3", "f4", "f5", "f6", "f7", \
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"f8", "f9", "f10","f11","f12","f13","f14","f15", \
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"f16","f17","f18","f19","f20","f21","f22","f23", \
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"f24","f25","f26","f27","f28","f29","f30","f31", \
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"pc", "ps", "cnd", "lr", "cnt", "xer", "mq" }
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/* Register numbers of various important registers.
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Note that some of these values are "real" register numbers,
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and correspond to the general registers of the machine,
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and some are "phony" register numbers which are too large
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to be actual register numbers as far as the user is concerned
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but do serve to get the desired values when passed to read_register. */
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#define FP_REGNUM 1 /* Contains address of executing stack frame */
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#define SP_REGNUM 1 /* Contains address of top of stack */
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#define TOC_REGNUM 2 /* TOC register */
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#define FP0_REGNUM 32 /* Floating point register 0 */
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#define GP0_REGNUM 0 /* GPR register 0 */
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#define FP0_REGNUM 32 /* FPR (Floating point) register 0 */
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#define FPLAST_REGNUM 63 /* Last floating point register */
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/* Special purpose registers... */
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/* P.S. keep these in the same order as in /usr/mstsave.h `mstsave' structure, for
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easier processing */
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#define PC_REGNUM 64 /* Program counter (instruction address %iar) */
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#define PS_REGNUM 65 /* Processor (or machine) status (%msr) */
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#define CR_REGNUM 66 /* Condition register */
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#define LR_REGNUM 67 /* Link register */
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#define CTR_REGNUM 68 /* Count register */
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#define XER_REGNUM 69 /* Fixed point exception registers */
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#define MQ_REGNUM 70 /* Multiply/quotient register */
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#define FIRST_SP_REGNUM 64 /* first special register number */
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#define LAST_SP_REGNUM 70 /* last special register number */
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/* Total amount of space needed to store our copies of the machine's
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register state, the array `registers'.
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32 4-byte gpr's
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32 8-byte fpr's
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7 4-byte special purpose registers,
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total 416 bytes. Keep some extra space for now, in case to add more. */
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#define REGISTER_BYTES 420
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/* Index within `registers' of the first byte of the space for
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register N. */
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#define REGISTER_BYTE(N) \
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( \
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((N) > FPLAST_REGNUM) ? ((((N) - FPLAST_REGNUM -1) * 4) + 384)\
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:((N) >= FP0_REGNUM) ? ((((N) - FP0_REGNUM) * 8) + 128) \
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:((N) * 4) )
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/* Number of bytes of storage in the actual machine representation
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for register N. */
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/* Note that the unsigned cast here forces the result of the
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subtractiion to very high positive values if N < FP0_REGNUM */
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#define REGISTER_RAW_SIZE(N) (((unsigned)(N) - FP0_REGNUM) < 32 ? 8 : 4)
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/* Number of bytes of storage in the program's representation
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for register N. On the RS6000, all regs are 4 bytes
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except the floating point regs which are 8-byte doubles. */
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#define REGISTER_VIRTUAL_SIZE(N) (((unsigned)(N) - FP0_REGNUM) < 32 ? 8 : 4)
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/* Largest value REGISTER_RAW_SIZE can have. */
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#define MAX_REGISTER_RAW_SIZE 8
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/* Largest value REGISTER_VIRTUAL_SIZE can have. */
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#define MAX_REGISTER_VIRTUAL_SIZE 8
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/* convert a dbx stab register number (from `r' declaration) to a gdb REGNUM */
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#define STAB_REG_TO_REGNUM(value) (value)
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/* Nonzero if register N requires conversion
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from raw format to virtual format.
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The register format for rs6000 floating point registers is always
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double, we need a conversion if the memory format is float. */
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#define REGISTER_CONVERTIBLE(N) ((N) >= FP0_REGNUM && (N) <= FPLAST_REGNUM)
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/* Convert data from raw format for register REGNUM in buffer FROM
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to virtual format with type TYPE in buffer TO. */
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#define REGISTER_CONVERT_TO_VIRTUAL(REGNUM,TYPE,FROM,TO) \
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{ \
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if (TYPE_LENGTH (TYPE) != REGISTER_RAW_SIZE (REGNUM)) \
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{ \
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double val = extract_floating ((FROM), REGISTER_RAW_SIZE (REGNUM)); \
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store_floating ((TO), TYPE_LENGTH (TYPE), val); \
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} \
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else \
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memcpy ((TO), (FROM), REGISTER_RAW_SIZE (REGNUM)); \
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}
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/* Convert data from virtual format with type TYPE in buffer FROM
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to raw format for register REGNUM in buffer TO. */
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#define REGISTER_CONVERT_TO_RAW(TYPE,REGNUM,FROM,TO) \
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{ \
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if (TYPE_LENGTH (TYPE) != REGISTER_RAW_SIZE (REGNUM)) \
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{ \
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double val = extract_floating ((FROM), TYPE_LENGTH (TYPE)); \
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store_floating ((TO), REGISTER_RAW_SIZE (REGNUM), val); \
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} \
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else \
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memcpy ((TO), (FROM), REGISTER_RAW_SIZE (REGNUM)); \
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}
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/* Return the GDB type object for the "standard" data type
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of data in register N. */
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#define REGISTER_VIRTUAL_TYPE(N) \
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(((unsigned)(N) - FP0_REGNUM) < 32 ? builtin_type_double : builtin_type_int)
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/* Store the address of the place in which to copy the structure the
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subroutine will return. This is called from call_function. */
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/* in RS6000, struct return addresses are passed as an extra parameter in r3.
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In function return, callee is not responsible of returning this address back.
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Since gdb needs to find it, we will store in a designated variable
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`rs6000_struct_return_address'. */
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extern CORE_ADDR rs6000_struct_return_address;
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#define STORE_STRUCT_RETURN(ADDR, SP) \
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{ write_register (3, (ADDR)); \
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rs6000_struct_return_address = (unsigned int)(ADDR); }
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/* Extract from an array REGBUF containing the (raw) register state
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a function return value of type TYPE, and copy that, in virtual format,
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into VALBUF. */
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/* #define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
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memcpy (VALBUF, REGBUF, TYPE_LENGTH (TYPE)) */
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#define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
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extract_return_value(TYPE,REGBUF,VALBUF)
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/* Write into appropriate registers a function return value
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of type TYPE, given in virtual format. */
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#define STORE_RETURN_VALUE(TYPE,VALBUF) \
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{ \
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if (TYPE_CODE (TYPE) == TYPE_CODE_FLT) \
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\
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/* Floating point values are returned starting from FPR1 and up. \
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Say a double_double_double type could be returned in \
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FPR1/FPR2/FPR3 triple. */ \
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\
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write_register_bytes (REGISTER_BYTE (FP0_REGNUM+1), (VALBUF), \
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TYPE_LENGTH (TYPE)); \
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else \
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/* Everything else is returned in GPR3 and up. */ \
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write_register_bytes (REGISTER_BYTE (GP0_REGNUM+3), (VALBUF), \
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TYPE_LENGTH (TYPE)); \
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}
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/* Extract from an array REGBUF containing the (raw) register state
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the address in which a function should return its structure value,
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as a CORE_ADDR (or an expression that can be used as one). */
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#define EXTRACT_STRUCT_VALUE_ADDRESS(REGBUF) rs6000_struct_return_address
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/* Describe the pointer in each stack frame to the previous stack frame
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(its caller). */
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/* FRAME_CHAIN takes a frame's nominal address
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and produces the frame's chain-pointer. */
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/* In the case of the RS6000, the frame's nominal address
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is the address of a 4-byte word containing the calling frame's address. */
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#define FRAME_CHAIN(thisframe) rs6000_frame_chain (thisframe)
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#ifdef __STDC__
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struct frame_info;
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#endif
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CORE_ADDR rs6000_frame_chain PARAMS ((struct frame_info *));
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/* Define other aspects of the stack frame. */
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/* A macro that tells us whether the function invocation represented
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by FI does not have a frame on the stack associated with it. If it
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does not, FRAMELESS is set to 1, else 0. */
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#define FRAMELESS_FUNCTION_INVOCATION(FI, FRAMELESS) \
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FRAMELESS = frameless_function_invocation (FI, 0)
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/* Functions calling alloca() change the value of the stack pointer. We
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need to use initial stack pointer (which is saved in r31 by gcc) in
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such cases. If a compiler emits traceback table, then we should use the
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alloca register specified in traceback table. FIXME. */
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/* Also, it is a good idea to cache information about frame's saved registers
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in the frame structure to speed things up. See tm-m88k.h. FIXME. */
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#define EXTRA_FRAME_INFO \
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CORE_ADDR initial_sp; /* initial stack pointer. */ \
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struct frame_saved_regs *cache_fsr; /* saved registers */
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#define INIT_FRAME_PC_FIRST(fromleaf, prev) \
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prev->pc = (fromleaf ? SAVED_PC_AFTER_CALL (prev->next) : \
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prev->next ? FRAME_SAVED_PC (prev->next) : read_pc ());
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#define INIT_FRAME_PC(fromleaf, prev) /* nothing */
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#define INIT_EXTRA_FRAME_INFO(fromleaf, fi) \
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fi->initial_sp = 0; \
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fi->cache_fsr = 0; \
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if (fi->next != (CORE_ADDR)0 \
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&& read_memory_integer (fi->frame, 4) == 0 \
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&& fi->pc < TEXT_SEGMENT_BASE) \
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/* We're in get_prev_frame_info */ \
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/* and this is a special signal frame. */ \
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/* (fi->pc will be something like 0x3f88 or 0x2790). */ \
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fi->signal_handler_caller = 1;
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/* Frameless function invocation in IBM RS/6000 is sometimes
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half-done. It perfectly sets up a new frame, e.g. a new frame (in
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fact stack) pointer, etc, but it doesn't save the %pc. We call
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frameless_function_invocation to tell us how to get the %pc. */
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#define FRAME_SAVED_PC(FRAME) \
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(frameless_function_invocation (FRAME, 1) \
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? SAVED_PC_AFTER_CALL (FRAME) \
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: read_memory_integer (rs6000_frame_chain (FRAME)+8, 4))
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#define FRAME_ARGS_ADDRESS(FI) \
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(((struct frame_info*)(FI))->initial_sp ? \
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((struct frame_info*)(FI))->initial_sp : \
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frame_initial_stack_address (FI))
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#define FRAME_LOCALS_ADDRESS(FI) FRAME_ARGS_ADDRESS(FI)
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/* Set VAL to the number of args passed to frame described by FI.
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Can set VAL to -1, meaning no way to tell. */
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/* We can't tell how many args there are
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now that the C compiler delays popping them. */
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#define FRAME_NUM_ARGS(val,fi) (val = -1)
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/* Return number of bytes at start of arglist that are not really args. */
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#define FRAME_ARGS_SKIP 8 /* Not sure on this. FIXMEmgo */
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/* Put here the code to store, into a struct frame_saved_regs,
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the addresses of the saved registers of frame described by FRAME_INFO.
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This includes special registers such as pc and fp saved in special
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ways in the stack frame. sp is even more special:
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the address we return for it IS the sp for the next frame. */
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||
/* In the following implementation for RS6000, we did *not* save sp. I am
|
||
not sure if it will be needed. The following macro takes care of gpr's
|
||
and fpr's only. */
|
||
|
||
#define FRAME_FIND_SAVED_REGS(FRAME_INFO, FRAME_SAVED_REGS) \
|
||
{ \
|
||
int ii; \
|
||
CORE_ADDR frame_addr, func_start; \
|
||
struct aix_framedata fdata; \
|
||
\
|
||
/* find the start of the function and collect info about its frame. */\
|
||
\
|
||
func_start = get_pc_function_start ((FRAME_INFO)->pc) + FUNCTION_START_OFFSET; \
|
||
function_frame_info (func_start, &fdata); \
|
||
memset (&(FRAME_SAVED_REGS), '\0', sizeof (FRAME_SAVED_REGS)); \
|
||
\
|
||
/* if there were any saved registers, figure out parent's stack pointer. */ \
|
||
frame_addr = 0; \
|
||
/* the following is true only if the frame doesn't have a call to alloca(), \
|
||
FIXME. */ \
|
||
if (fdata.saved_fpr >= 0 || fdata.saved_gpr >= 0) { \
|
||
if ((FRAME_INFO)->prev && (FRAME_INFO)->prev->frame) \
|
||
frame_addr = (FRAME_INFO)->prev->frame; \
|
||
else \
|
||
frame_addr = read_memory_integer ((FRAME_INFO)->frame, 4); \
|
||
} \
|
||
\
|
||
/* if != -1, fdata.saved_fpr is the smallest number of saved_fpr. All fpr's \
|
||
from saved_fpr to fp31 are saved right underneath caller stack pointer, \
|
||
starting from fp31 first. */ \
|
||
\
|
||
if (fdata.saved_fpr >= 0) { \
|
||
for (ii=31; ii >= fdata.saved_fpr; --ii) \
|
||
(FRAME_SAVED_REGS).regs [FP0_REGNUM + ii] = frame_addr - ((32 - ii) * 8); \
|
||
frame_addr -= (32 - fdata.saved_fpr) * 8; \
|
||
} \
|
||
\
|
||
/* if != -1, fdata.saved_gpr is the smallest number of saved_gpr. All gpr's \
|
||
from saved_gpr to gpr31 are saved right under saved fprs, starting \
|
||
from r31 first. */ \
|
||
\
|
||
if (fdata.saved_gpr >= 0) \
|
||
for (ii=31; ii >= fdata.saved_gpr; --ii) \
|
||
(FRAME_SAVED_REGS).regs [ii] = frame_addr - ((32 - ii) * 4); \
|
||
}
|
||
|
||
|
||
/* Things needed for making the inferior call functions. */
|
||
|
||
/* Push an empty stack frame, to record the current PC, etc. */
|
||
/* Change these names into rs6k_{push, pop}_frame(). FIXMEmgo. */
|
||
|
||
#define PUSH_DUMMY_FRAME push_dummy_frame ()
|
||
|
||
/* Discard from the stack the innermost frame,
|
||
restoring all saved registers. */
|
||
|
||
#define POP_FRAME pop_frame ()
|
||
|
||
/* This sequence of words is the instructions:
|
||
|
||
mflr r0 // 0x7c0802a6
|
||
// save fpr's
|
||
stfd r?, num(r1) // 0xd8010000 there should be 32 of this??
|
||
// save gpr's
|
||
stm r0, num(r1) // 0xbc010000
|
||
stu r1, num(r1) // 0x94210000
|
||
|
||
// the function we want to branch might be in a different load
|
||
// segment. reset the toc register. Note that the actual toc address
|
||
// will be fix by fix_call_dummy () along with function address.
|
||
|
||
st r2, 0x14(r1) // 0x90410014 save toc register
|
||
liu r2, 0x1234 // 0x3c401234 reset a new toc value 0x12345678
|
||
oril r2, r2,0x5678 // 0x60425678
|
||
|
||
// load absolute address 0x12345678 to r0
|
||
liu r0, 0x1234 // 0x3c001234
|
||
oril r0, r0,0x5678 // 0x60005678
|
||
mtctr r0 // 0x7c0903a6 ctr <- r0
|
||
bctrl // 0x4e800421 jump subroutine 0x12345678 (%ctr)
|
||
cror 0xf, 0xf, 0xf // 0x4def7b82
|
||
brpt // 0x7d821008, breakpoint
|
||
cror 0xf, 0xf, 0xf // 0x4def7b82 (for 8 byte alignment)
|
||
|
||
|
||
We actually start executing by saving the toc register first, since the pushing
|
||
of the registers is done by PUSH_DUMMY_FRAME. If this were real code,
|
||
the arguments for the function called by the `bctrl' would be pushed
|
||
between the `stu' and the `bctrl', and we could allow it to execute through.
|
||
But the arguments have to be pushed by GDB after the PUSH_DUMMY_FRAME is done,
|
||
and we cannot allow to push the registers again.
|
||
*/
|
||
|
||
#define CALL_DUMMY {0x7c0802a6, 0xd8010000, 0xbc010000, 0x94210000, \
|
||
0x90410014, 0x3c401234, 0x60425678, \
|
||
0x3c001234, 0x60005678, 0x7c0903a6, 0x4e800421, \
|
||
0x4def7b82, 0x7d821008, 0x4def7b82 }
|
||
|
||
|
||
/* keep this as multiple of 8 (%sp requires 8 byte alignment) */
|
||
#define CALL_DUMMY_LENGTH 56
|
||
|
||
#define CALL_DUMMY_START_OFFSET 16
|
||
|
||
/* Insert the specified number of args and function address
|
||
into a call sequence of the above form stored at DUMMYNAME. */
|
||
|
||
#define FIX_CALL_DUMMY(dummyname, pc, fun, nargs, args, type, using_gcc) \
|
||
fix_call_dummy(dummyname, pc, fun, nargs, type)
|
||
|
||
/* Flag for machine-specific stuff in shared files. FIXME */
|
||
#define IBM6000_TARGET
|
||
|
||
/* RS6000/AIX does not support PT_STEP. Has to be simulated. */
|
||
|
||
#define NO_SINGLE_STEP
|