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-rw-r--r--gdb/alpha-tdep.c1410
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diff --git a/gdb/alpha-tdep.c b/gdb/alpha-tdep.c
new file mode 100644
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--- /dev/null
+++ b/gdb/alpha-tdep.c
@@ -0,0 +1,1410 @@
+/* Target-dependent code for the ALPHA architecture, for GDB, the GNU Debugger.
+ Copyright 1993, 94, 95, 96, 97, 1998 Free Software Foundation, Inc.
+
+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 "inferior.h"
+#include "symtab.h"
+#include "value.h"
+#include "gdbcmd.h"
+#include "gdbcore.h"
+#include "dis-asm.h"
+#include "symfile.h"
+#include "objfiles.h"
+#include "gdb_string.h"
+
+/* FIXME: Some of this code should perhaps be merged with mips-tdep.c. */
+
+/* Prototypes for local functions. */
+
+static alpha_extra_func_info_t push_sigtramp_desc PARAMS ((CORE_ADDR low_addr));
+
+static CORE_ADDR read_next_frame_reg PARAMS ((struct frame_info *, int));
+
+static CORE_ADDR heuristic_proc_start PARAMS ((CORE_ADDR));
+
+static alpha_extra_func_info_t heuristic_proc_desc PARAMS ((CORE_ADDR,
+ CORE_ADDR,
+ struct frame_info *));
+
+static alpha_extra_func_info_t find_proc_desc PARAMS ((CORE_ADDR,
+ struct frame_info *));
+
+#if 0
+static int alpha_in_lenient_prologue PARAMS ((CORE_ADDR, CORE_ADDR));
+#endif
+
+static void reinit_frame_cache_sfunc PARAMS ((char *, int,
+ struct cmd_list_element *));
+
+static CORE_ADDR after_prologue PARAMS ((CORE_ADDR pc,
+ alpha_extra_func_info_t proc_desc));
+
+static int alpha_in_prologue PARAMS ((CORE_ADDR pc,
+ alpha_extra_func_info_t proc_desc));
+
+/* Heuristic_proc_start may hunt through the text section for a long
+ time across a 2400 baud serial line. Allows the user to limit this
+ search. */
+static unsigned int heuristic_fence_post = 0;
+
+/* Layout of a stack frame on the alpha:
+
+ | |
+ pdr members: | 7th ... nth arg, |
+ | `pushed' by caller. |
+ | |
+----------------|-------------------------------|<-- old_sp == vfp
+ ^ ^ ^ ^ | |
+ | | | | | |
+ | |localoff | Copies of 1st .. 6th |
+ | | | | | argument if necessary. |
+ | | | v | |
+ | | | --- |-------------------------------|<-- FRAME_LOCALS_ADDRESS
+ | | | | |
+ | | | | Locals and temporaries. |
+ | | | | |
+ | | | |-------------------------------|
+ | | | | |
+ |-fregoffset | Saved float registers. |
+ | | | | F9 |
+ | | | | . |
+ | | | | . |
+ | | | | F2 |
+ | | v | |
+ | | -------|-------------------------------|
+ | | | |
+ | | | Saved registers. |
+ | | | S6 |
+ |-regoffset | . |
+ | | | . |
+ | | | S0 |
+ | | | pdr.pcreg |
+ | v | |
+ | ----------|-------------------------------|
+ | | |
+ frameoffset | Argument build area, gets |
+ | | 7th ... nth arg for any |
+ | | called procedure. |
+ v | |
+ -------------|-------------------------------|<-- sp
+ | |
+*/
+
+#define PROC_LOW_ADDR(proc) ((proc)->pdr.adr) /* least address */
+#define PROC_HIGH_ADDR(proc) ((proc)->pdr.iline) /* upper address bound */
+#define PROC_DUMMY_FRAME(proc) ((proc)->pdr.iopt) /* frame for CALL_DUMMY */
+#define PROC_FRAME_OFFSET(proc) ((proc)->pdr.frameoffset)
+#define PROC_FRAME_REG(proc) ((proc)->pdr.framereg)
+#define PROC_REG_MASK(proc) ((proc)->pdr.regmask)
+#define PROC_FREG_MASK(proc) ((proc)->pdr.fregmask)
+#define PROC_REG_OFFSET(proc) ((proc)->pdr.regoffset)
+#define PROC_FREG_OFFSET(proc) ((proc)->pdr.fregoffset)
+#define PROC_PC_REG(proc) ((proc)->pdr.pcreg)
+#define PROC_LOCALOFF(proc) ((proc)->pdr.localoff)
+#define PROC_SYMBOL(proc) (*(struct symbol**)&(proc)->pdr.isym)
+#define _PROC_MAGIC_ 0x0F0F0F0F
+#define PROC_DESC_IS_DUMMY(proc) ((proc)->pdr.isym == _PROC_MAGIC_)
+#define SET_PROC_DESC_IS_DUMMY(proc) ((proc)->pdr.isym = _PROC_MAGIC_)
+
+struct linked_proc_info
+{
+ struct alpha_extra_func_info info;
+ struct linked_proc_info *next;
+} *linked_proc_desc_table = NULL;
+
+
+/* Under GNU/Linux, signal handler invocations can be identified by the
+ designated code sequence that is used to return from a signal
+ handler. In particular, the return address of a signal handler
+ points to the following sequence (the first instruction is quadword
+ aligned):
+
+ bis $30,$30,$16
+ addq $31,0x67,$0
+ call_pal callsys
+
+ Each instruction has a unique encoding, so we simply attempt to
+ match the instruction the pc is pointing to with any of the above
+ instructions. If there is a hit, we know the offset to the start
+ of the designated sequence and can then check whether we really are
+ executing in a designated sequence. If not, -1 is returned,
+ otherwise the offset from the start of the desingated sequence is
+ returned.
+
+ There is a slight chance of false hits: code could jump into the
+ middle of the designated sequence, in which case there is no
+ guarantee that we are in the middle of a sigreturn syscall. Don't
+ think this will be a problem in praxis, though.
+*/
+
+long
+alpha_linux_sigtramp_offset (CORE_ADDR pc)
+{
+ unsigned int i[3], w;
+ long off;
+
+ if (read_memory_nobpt(pc, (char *) &w, 4) != 0)
+ return -1;
+
+ off = -1;
+ switch (w)
+ {
+ case 0x47de0410: off = 0; break; /* bis $30,$30,$16 */
+ case 0x43ecf400: off = 4; break; /* addq $31,0x67,$0 */
+ case 0x00000083: off = 8; break; /* call_pal callsys */
+ default: return -1;
+ }
+ pc -= off;
+ if (pc & 0x7)
+ {
+ /* designated sequence is not quadword aligned */
+ return -1;
+ }
+
+ if (read_memory_nobpt(pc, (char *) i, sizeof(i)) != 0)
+ return -1;
+
+ if (i[0] == 0x47de0410 && i[1] == 0x43ecf400 && i[2] == 0x00000083)
+ return off;
+
+ return -1;
+}
+
+
+/* Under OSF/1, the __sigtramp routine is frameless and has a frame
+ size of zero, but we are able to backtrace through it. */
+CORE_ADDR
+alpha_osf_skip_sigtramp_frame (frame, pc)
+ struct frame_info *frame;
+ CORE_ADDR pc;
+{
+ char *name;
+ find_pc_partial_function (pc, &name, (CORE_ADDR *)NULL, (CORE_ADDR *)NULL);
+ if (IN_SIGTRAMP (pc, name))
+ return frame->frame;
+ else
+ return 0;
+}
+
+
+/* Dynamically create a signal-handler caller procedure descriptor for
+ the signal-handler return code starting at address LOW_ADDR. The
+ descriptor is added to the linked_proc_desc_table. */
+
+static alpha_extra_func_info_t
+push_sigtramp_desc (low_addr)
+ CORE_ADDR low_addr;
+{
+ struct linked_proc_info *link;
+ alpha_extra_func_info_t proc_desc;
+
+ link = (struct linked_proc_info *)
+ xmalloc (sizeof (struct linked_proc_info));
+ link->next = linked_proc_desc_table;
+ linked_proc_desc_table = link;
+
+ proc_desc = &link->info;
+
+ proc_desc->numargs = 0;
+ PROC_LOW_ADDR (proc_desc) = low_addr;
+ PROC_HIGH_ADDR (proc_desc) = low_addr + 3 * 4;
+ PROC_DUMMY_FRAME (proc_desc) = 0;
+ PROC_FRAME_OFFSET (proc_desc) = 0x298; /* sizeof(struct sigcontext_struct) */
+ PROC_FRAME_REG (proc_desc) = SP_REGNUM;
+ PROC_REG_MASK (proc_desc) = 0xffff;
+ PROC_FREG_MASK (proc_desc) = 0xffff;
+ PROC_PC_REG (proc_desc) = 26;
+ PROC_LOCALOFF (proc_desc) = 0;
+ SET_PROC_DESC_IS_DYN_SIGTRAMP (proc_desc);
+ return (proc_desc);
+}
+
+
+/* Guaranteed to set frame->saved_regs to some values (it never leaves it
+ NULL). */
+
+void
+alpha_find_saved_regs (frame)
+ struct frame_info *frame;
+{
+ int ireg;
+ CORE_ADDR reg_position;
+ unsigned long mask;
+ alpha_extra_func_info_t proc_desc;
+ int returnreg;
+
+ frame_saved_regs_zalloc (frame);
+
+ /* If it is the frame for __sigtramp, the saved registers are located
+ in a sigcontext structure somewhere on the stack. __sigtramp
+ passes a pointer to the sigcontext structure on the stack.
+ If the stack layout for __sigtramp changes, or if sigcontext offsets
+ change, we might have to update this code. */
+#ifndef SIGFRAME_PC_OFF
+#define SIGFRAME_PC_OFF (2 * 8)
+#define SIGFRAME_REGSAVE_OFF (4 * 8)
+#define SIGFRAME_FPREGSAVE_OFF (SIGFRAME_REGSAVE_OFF + 32 * 8 + 8)
+#endif
+ if (frame->signal_handler_caller)
+ {
+ CORE_ADDR sigcontext_addr;
+
+ sigcontext_addr = SIGCONTEXT_ADDR (frame);
+ for (ireg = 0; ireg < 32; ireg++)
+ {
+ reg_position = sigcontext_addr + SIGFRAME_REGSAVE_OFF + ireg * 8;
+ frame->saved_regs[ireg] = reg_position;
+ }
+ for (ireg = 0; ireg < 32; ireg++)
+ {
+ reg_position = sigcontext_addr + SIGFRAME_FPREGSAVE_OFF + ireg * 8;
+ frame->saved_regs[FP0_REGNUM + ireg] = reg_position;
+ }
+ frame->saved_regs[PC_REGNUM] = sigcontext_addr + SIGFRAME_PC_OFF;
+ return;
+ }
+
+ proc_desc = frame->proc_desc;
+ if (proc_desc == NULL)
+ /* I'm not sure how/whether this can happen. Normally when we can't
+ find a proc_desc, we "synthesize" one using heuristic_proc_desc
+ and set the saved_regs right away. */
+ return;
+
+ /* Fill in the offsets for the registers which gen_mask says
+ were saved. */
+
+ reg_position = frame->frame + PROC_REG_OFFSET (proc_desc);
+ mask = PROC_REG_MASK (proc_desc);
+
+ returnreg = PROC_PC_REG (proc_desc);
+
+ /* Note that RA is always saved first, regardless of its actual
+ register number. */
+ if (mask & (1 << returnreg))
+ {
+ frame->saved_regs[returnreg] = reg_position;
+ reg_position += 8;
+ mask &= ~(1 << returnreg); /* Clear bit for RA so we
+ don't save again later. */
+ }
+
+ for (ireg = 0; ireg <= 31 ; ++ireg)
+ if (mask & (1 << ireg))
+ {
+ frame->saved_regs[ireg] = reg_position;
+ reg_position += 8;
+ }
+
+ /* Fill in the offsets for the registers which float_mask says
+ were saved. */
+
+ reg_position = frame->frame + PROC_FREG_OFFSET (proc_desc);
+ mask = PROC_FREG_MASK (proc_desc);
+
+ for (ireg = 0; ireg <= 31 ; ++ireg)
+ if (mask & (1 << ireg))
+ {
+ frame->saved_regs[FP0_REGNUM+ireg] = reg_position;
+ reg_position += 8;
+ }
+
+ frame->saved_regs[PC_REGNUM] = frame->saved_regs[returnreg];
+}
+
+static CORE_ADDR
+read_next_frame_reg(fi, regno)
+ struct frame_info *fi;
+ int regno;
+{
+ for (; fi; fi = fi->next)
+ {
+ /* We have to get the saved sp from the sigcontext
+ if it is a signal handler frame. */
+ if (regno == SP_REGNUM && !fi->signal_handler_caller)
+ return fi->frame;
+ else
+ {
+ if (fi->saved_regs == NULL)
+ alpha_find_saved_regs (fi);
+ if (fi->saved_regs[regno])
+ return read_memory_integer(fi->saved_regs[regno], 8);
+ }
+ }
+ return read_register(regno);
+}
+
+CORE_ADDR
+alpha_frame_saved_pc(frame)
+ struct frame_info *frame;
+{
+ alpha_extra_func_info_t proc_desc = frame->proc_desc;
+ /* We have to get the saved pc from the sigcontext
+ if it is a signal handler frame. */
+ int pcreg = frame->signal_handler_caller ? PC_REGNUM : frame->pc_reg;
+
+ if (proc_desc && PROC_DESC_IS_DUMMY(proc_desc))
+ return read_memory_integer(frame->frame - 8, 8);
+
+ return read_next_frame_reg(frame, pcreg);
+}
+
+CORE_ADDR
+alpha_saved_pc_after_call (frame)
+ struct frame_info *frame;
+{
+ CORE_ADDR pc = frame->pc;
+ CORE_ADDR tmp;
+ alpha_extra_func_info_t proc_desc;
+ int pcreg;
+
+ /* Skip over shared library trampoline if necessary. */
+ tmp = SKIP_TRAMPOLINE_CODE (pc);
+ if (tmp != 0)
+ pc = tmp;
+
+ proc_desc = find_proc_desc (pc, frame->next);
+ pcreg = proc_desc ? PROC_PC_REG (proc_desc) : RA_REGNUM;
+
+ if (frame->signal_handler_caller)
+ return alpha_frame_saved_pc (frame);
+ else
+ return read_register (pcreg);
+}
+
+
+static struct alpha_extra_func_info temp_proc_desc;
+static struct frame_saved_regs temp_saved_regs;
+
+/* Nonzero if instruction at PC is a return instruction. "ret
+ $zero,($ra),1" on alpha. */
+
+static int
+alpha_about_to_return (pc)
+ CORE_ADDR pc;
+{
+ return read_memory_integer (pc, 4) == 0x6bfa8001;
+}
+
+
+
+/* This fencepost looks highly suspicious to me. Removing it also
+ seems suspicious as it could affect remote debugging across serial
+ lines. */
+
+static CORE_ADDR
+heuristic_proc_start(pc)
+ CORE_ADDR pc;
+{
+ CORE_ADDR start_pc = pc;
+ CORE_ADDR fence = start_pc - heuristic_fence_post;
+
+ if (start_pc == 0) return 0;
+
+ if (heuristic_fence_post == UINT_MAX
+ || fence < VM_MIN_ADDRESS)
+ fence = VM_MIN_ADDRESS;
+
+ /* search back for previous return */
+ for (start_pc -= 4; ; start_pc -= 4)
+ if (start_pc < fence)
+ {
+ /* It's not clear to me why we reach this point when
+ stop_soon_quietly, but with this test, at least we
+ don't print out warnings for every child forked (eg, on
+ decstation). 22apr93 rich@cygnus.com. */
+ if (!stop_soon_quietly)
+ {
+ static int blurb_printed = 0;
+
+ if (fence == VM_MIN_ADDRESS)
+ warning("Hit beginning of text section without finding");
+ else
+ warning("Hit heuristic-fence-post without finding");
+
+ warning("enclosing function for address 0x%lx", pc);
+ if (!blurb_printed)
+ {
+ printf_filtered ("\
+This warning occurs if you are debugging a function without any symbols\n\
+(for example, in a stripped executable). In that case, you may wish to\n\
+increase the size of the search with the `set heuristic-fence-post' command.\n\
+\n\
+Otherwise, you told GDB there was a function where there isn't one, or\n\
+(more likely) you have encountered a bug in GDB.\n");
+ blurb_printed = 1;
+ }
+ }
+
+ return 0;
+ }
+ else if (alpha_about_to_return (start_pc))
+ break;
+
+ start_pc += 4; /* skip return */
+ return start_pc;
+}
+
+static alpha_extra_func_info_t
+heuristic_proc_desc(start_pc, limit_pc, next_frame)
+ CORE_ADDR start_pc, limit_pc;
+ struct frame_info *next_frame;
+{
+ CORE_ADDR sp = read_next_frame_reg (next_frame, SP_REGNUM);
+ CORE_ADDR cur_pc;
+ int frame_size;
+ int has_frame_reg = 0;
+ unsigned long reg_mask = 0;
+ int pcreg = -1;
+
+ if (start_pc == 0)
+ return NULL;
+ memset (&temp_proc_desc, '\0', sizeof(temp_proc_desc));
+ memset (&temp_saved_regs, '\0', sizeof(struct frame_saved_regs));
+ PROC_LOW_ADDR (&temp_proc_desc) = start_pc;
+
+ if (start_pc + 200 < limit_pc)
+ limit_pc = start_pc + 200;
+ frame_size = 0;
+ for (cur_pc = start_pc; cur_pc < limit_pc; cur_pc += 4)
+ {
+ char buf[4];
+ unsigned long word;
+ int status;
+
+ status = read_memory_nobpt (cur_pc, buf, 4);
+ if (status)
+ memory_error (status, cur_pc);
+ word = extract_unsigned_integer (buf, 4);
+
+ if ((word & 0xffff0000) == 0x23de0000) /* lda $sp,n($sp) */
+ {
+ if (word & 0x8000)
+ frame_size += (-word) & 0xffff;
+ else
+ /* Exit loop if a positive stack adjustment is found, which
+ usually means that the stack cleanup code in the function
+ epilogue is reached. */
+ break;
+ }
+ else if ((word & 0xfc1f0000) == 0xb41e0000 /* stq reg,n($sp) */
+ && (word & 0xffff0000) != 0xb7fe0000) /* reg != $zero */
+ {
+ int reg = (word & 0x03e00000) >> 21;
+ reg_mask |= 1 << reg;
+ temp_saved_regs.regs[reg] = sp + (short)word;
+
+ /* Starting with OSF/1-3.2C, the system libraries are shipped
+ without local symbols, but they still contain procedure
+ descriptors without a symbol reference. GDB is currently
+ unable to find these procedure descriptors and uses
+ heuristic_proc_desc instead.
+ As some low level compiler support routines (__div*, __add*)
+ use a non-standard return address register, we have to
+ add some heuristics to determine the return address register,
+ or stepping over these routines will fail.
+ Usually the return address register is the first register
+ saved on the stack, but assembler optimization might
+ rearrange the register saves.
+ So we recognize only a few registers (t7, t9, ra) within
+ the procedure prologue as valid return address registers.
+ If we encounter a return instruction, we extract the
+ the return address register from it.
+
+ FIXME: Rewriting GDB to access the procedure descriptors,
+ e.g. via the minimal symbol table, might obviate this hack. */
+ if (pcreg == -1
+ && cur_pc < (start_pc + 80)
+ && (reg == T7_REGNUM || reg == T9_REGNUM || reg == RA_REGNUM))
+ pcreg = reg;
+ }
+ else if ((word & 0xffe0ffff) == 0x6be08001) /* ret zero,reg,1 */
+ pcreg = (word >> 16) & 0x1f;
+ else if (word == 0x47de040f) /* bis sp,sp fp */
+ has_frame_reg = 1;
+ }
+ if (pcreg == -1)
+ {
+ /* If we haven't found a valid return address register yet,
+ keep searching in the procedure prologue. */
+ while (cur_pc < (limit_pc + 80) && cur_pc < (start_pc + 80))
+ {
+ char buf[4];
+ unsigned long word;
+
+ if (read_memory_nobpt (cur_pc, buf, 4))
+ break;
+ cur_pc += 4;
+ word = extract_unsigned_integer (buf, 4);
+
+ if ((word & 0xfc1f0000) == 0xb41e0000 /* stq reg,n($sp) */
+ && (word & 0xffff0000) != 0xb7fe0000) /* reg != $zero */
+ {
+ int reg = (word & 0x03e00000) >> 21;
+ if (reg == T7_REGNUM || reg == T9_REGNUM || reg == RA_REGNUM)
+ {
+ pcreg = reg;
+ break;
+ }
+ }
+ else if ((word & 0xffe0ffff) == 0x6be08001) /* ret zero,reg,1 */
+ {
+ pcreg = (word >> 16) & 0x1f;
+ break;
+ }
+ }
+ }
+
+ if (has_frame_reg)
+ PROC_FRAME_REG(&temp_proc_desc) = GCC_FP_REGNUM;
+ else
+ PROC_FRAME_REG(&temp_proc_desc) = SP_REGNUM;
+ PROC_FRAME_OFFSET(&temp_proc_desc) = frame_size;
+ PROC_REG_MASK(&temp_proc_desc) = reg_mask;
+ PROC_PC_REG(&temp_proc_desc) = (pcreg == -1) ? RA_REGNUM : pcreg;
+ PROC_LOCALOFF(&temp_proc_desc) = 0; /* XXX - bogus */
+ return &temp_proc_desc;
+}
+
+/* This returns the PC of the first inst after the prologue. If we can't
+ find the prologue, then return 0. */
+
+static CORE_ADDR
+after_prologue (pc, proc_desc)
+ CORE_ADDR pc;
+ alpha_extra_func_info_t proc_desc;
+{
+ struct symtab_and_line sal;
+ CORE_ADDR func_addr, func_end;
+
+ if (!proc_desc)
+ proc_desc = find_proc_desc (pc, NULL);
+
+ if (proc_desc)
+ {
+ if (PROC_DESC_IS_DYN_SIGTRAMP (proc_desc))
+ return PROC_LOW_ADDR (proc_desc); /* "prologue" is in kernel */
+
+ /* If function is frameless, then we need to do it the hard way. I
+ strongly suspect that frameless always means prologueless... */
+ if (PROC_FRAME_REG (proc_desc) == SP_REGNUM
+ && PROC_FRAME_OFFSET (proc_desc) == 0)
+ return 0;
+ }
+
+ if (!find_pc_partial_function (pc, NULL, &func_addr, &func_end))
+ return 0; /* Unknown */
+
+ sal = find_pc_line (func_addr, 0);
+
+ if (sal.end < func_end)
+ return sal.end;
+
+ /* The line after the prologue is after the end of the function. In this
+ case, tell the caller to find the prologue the hard way. */
+
+ return 0;
+}
+
+/* Return non-zero if we *might* be in a function prologue. Return zero if we
+ are definitively *not* in a function prologue. */
+
+static int
+alpha_in_prologue (pc, proc_desc)
+ CORE_ADDR pc;
+ alpha_extra_func_info_t proc_desc;
+{
+ CORE_ADDR after_prologue_pc;
+
+ after_prologue_pc = after_prologue (pc, proc_desc);
+
+ if (after_prologue_pc == 0
+ || pc < after_prologue_pc)
+ return 1;
+ else
+ return 0;
+}
+
+static alpha_extra_func_info_t
+find_proc_desc (pc, next_frame)
+ CORE_ADDR pc;
+ struct frame_info *next_frame;
+{
+ alpha_extra_func_info_t proc_desc;
+ struct block *b;
+ struct symbol *sym;
+ CORE_ADDR startaddr;
+
+ /* Try to get the proc_desc from the linked call dummy proc_descs
+ if the pc is in the call dummy.
+ This is hairy. In the case of nested dummy calls we have to find the
+ right proc_desc, but we might not yet know the frame for the dummy
+ as it will be contained in the proc_desc we are searching for.
+ So we have to find the proc_desc whose frame is closest to the current
+ stack pointer. */
+
+ if (PC_IN_CALL_DUMMY (pc, 0, 0))
+ {
+ struct linked_proc_info *link;
+ CORE_ADDR sp = read_next_frame_reg (next_frame, SP_REGNUM);
+ alpha_extra_func_info_t found_proc_desc = NULL;
+ long min_distance = LONG_MAX;
+
+ for (link = linked_proc_desc_table; link; link = link->next)
+ {
+ long distance = (CORE_ADDR) PROC_DUMMY_FRAME (&link->info) - sp;
+ if (distance > 0 && distance < min_distance)
+ {
+ min_distance = distance;
+ found_proc_desc = &link->info;
+ }
+ }
+ if (found_proc_desc != NULL)
+ return found_proc_desc;
+ }
+
+ b = block_for_pc(pc);
+
+ find_pc_partial_function (pc, NULL, &startaddr, NULL);
+ if (b == NULL)
+ sym = NULL;
+ else
+ {
+ if (startaddr > BLOCK_START (b))
+ /* This is the "pathological" case referred to in a comment in
+ print_frame_info. It might be better to move this check into
+ symbol reading. */
+ sym = NULL;
+ else
+ sym = lookup_symbol (MIPS_EFI_SYMBOL_NAME, b, LABEL_NAMESPACE,
+ 0, NULL);
+ }
+
+ /* If we never found a PDR for this function in symbol reading, then
+ examine prologues to find the information. */
+ if (sym && ((mips_extra_func_info_t) SYMBOL_VALUE (sym))->pdr.framereg == -1)
+ sym = NULL;
+
+ if (sym)
+ {
+ /* IF this is the topmost frame AND
+ * (this proc does not have debugging information OR
+ * the PC is in the procedure prologue)
+ * THEN create a "heuristic" proc_desc (by analyzing
+ * the actual code) to replace the "official" proc_desc.
+ */
+ proc_desc = (alpha_extra_func_info_t)SYMBOL_VALUE(sym);
+ if (next_frame == NULL)
+ {
+ if (PROC_DESC_IS_DUMMY (proc_desc) || alpha_in_prologue (pc, proc_desc))
+ {
+ alpha_extra_func_info_t found_heuristic =
+ heuristic_proc_desc (PROC_LOW_ADDR (proc_desc),
+ pc, next_frame);
+ if (found_heuristic)
+ {
+ PROC_LOCALOFF (found_heuristic) =
+ PROC_LOCALOFF (proc_desc);
+ PROC_PC_REG (found_heuristic) = PROC_PC_REG (proc_desc);
+ proc_desc = found_heuristic;
+ }
+ }
+ }
+ }
+ else
+ {
+ long offset;
+
+ /* Is linked_proc_desc_table really necessary? It only seems to be used
+ by procedure call dummys. However, the procedures being called ought
+ to have their own proc_descs, and even if they don't,
+ heuristic_proc_desc knows how to create them! */
+
+ register struct linked_proc_info *link;
+ for (link = linked_proc_desc_table; link; link = link->next)
+ if (PROC_LOW_ADDR(&link->info) <= pc
+ && PROC_HIGH_ADDR(&link->info) > pc)
+ return &link->info;
+
+ /* If PC is inside a dynamically generated sigtramp handler,
+ create and push a procedure descriptor for that code: */
+ offset = DYNAMIC_SIGTRAMP_OFFSET (pc);
+ if (offset >= 0)
+ return push_sigtramp_desc (pc - offset);
+
+ /* If heuristic_fence_post is non-zero, determine the procedure
+ start address by examining the instructions.
+ This allows us to find the start address of static functions which
+ have no symbolic information, as startaddr would have been set to
+ the preceding global function start address by the
+ find_pc_partial_function call above. */
+ if (startaddr == 0 || heuristic_fence_post != 0)
+ startaddr = heuristic_proc_start (pc);
+
+ proc_desc =
+ heuristic_proc_desc (startaddr, pc, next_frame);
+ }
+ return proc_desc;
+}
+
+alpha_extra_func_info_t cached_proc_desc;
+
+CORE_ADDR
+alpha_frame_chain(frame)
+ struct frame_info *frame;
+{
+ alpha_extra_func_info_t proc_desc;
+ CORE_ADDR saved_pc = FRAME_SAVED_PC(frame);
+
+ if (saved_pc == 0 || inside_entry_file (saved_pc))
+ return 0;
+
+ proc_desc = find_proc_desc(saved_pc, frame);
+ if (!proc_desc)
+ return 0;
+
+ cached_proc_desc = proc_desc;
+
+ /* Fetch the frame pointer for a dummy frame from the procedure
+ descriptor. */
+ if (PROC_DESC_IS_DUMMY(proc_desc))
+ return (CORE_ADDR) PROC_DUMMY_FRAME(proc_desc);
+
+ /* If no frame pointer and frame size is zero, we must be at end
+ of stack (or otherwise hosed). If we don't check frame size,
+ we loop forever if we see a zero size frame. */
+ if (PROC_FRAME_REG (proc_desc) == SP_REGNUM
+ && PROC_FRAME_OFFSET (proc_desc) == 0
+ /* The previous frame from a sigtramp frame might be frameless
+ and have frame size zero. */
+ && !frame->signal_handler_caller)
+ return FRAME_PAST_SIGTRAMP_FRAME (frame, saved_pc);
+ else
+ return read_next_frame_reg(frame, PROC_FRAME_REG(proc_desc))
+ + PROC_FRAME_OFFSET(proc_desc);
+}
+
+void
+init_extra_frame_info (frame)
+ struct frame_info *frame;
+{
+ /* Use proc_desc calculated in frame_chain */
+ alpha_extra_func_info_t proc_desc =
+ frame->next ? cached_proc_desc : find_proc_desc(frame->pc, frame->next);
+
+ frame->saved_regs = NULL;
+ frame->localoff = 0;
+ frame->pc_reg = RA_REGNUM;
+ frame->proc_desc = proc_desc == &temp_proc_desc ? 0 : proc_desc;
+ if (proc_desc)
+ {
+ /* Get the locals offset and the saved pc register from the
+ procedure descriptor, they are valid even if we are in the
+ middle of the prologue. */
+ frame->localoff = PROC_LOCALOFF(proc_desc);
+ frame->pc_reg = PROC_PC_REG(proc_desc);
+
+ /* Fixup frame-pointer - only needed for top frame */
+
+ /* Fetch the frame pointer for a dummy frame from the procedure
+ descriptor. */
+ if (PROC_DESC_IS_DUMMY(proc_desc))
+ frame->frame = (CORE_ADDR) PROC_DUMMY_FRAME(proc_desc);
+
+ /* This may not be quite right, if proc has a real frame register.
+ Get the value of the frame relative sp, procedure might have been
+ interrupted by a signal at it's very start. */
+ else if (frame->pc == PROC_LOW_ADDR (proc_desc)
+ && !PROC_DESC_IS_DYN_SIGTRAMP (proc_desc))
+ frame->frame = read_next_frame_reg (frame->next, SP_REGNUM);
+ else
+ frame->frame = read_next_frame_reg (frame->next, PROC_FRAME_REG (proc_desc))
+ + PROC_FRAME_OFFSET (proc_desc);
+
+ if (proc_desc == &temp_proc_desc)
+ {
+ char *name;
+
+ /* Do not set the saved registers for a sigtramp frame,
+ alpha_find_saved_registers will do that for us.
+ We can't use frame->signal_handler_caller, it is not yet set. */
+ find_pc_partial_function (frame->pc, &name,
+ (CORE_ADDR *)NULL,(CORE_ADDR *)NULL);
+ if (!IN_SIGTRAMP (frame->pc, name))
+ {
+ frame->saved_regs = (CORE_ADDR*)
+ frame_obstack_alloc (SIZEOF_FRAME_SAVED_REGS);
+ memcpy (frame->saved_regs, temp_saved_regs.regs, SIZEOF_FRAME_SAVED_REGS);
+ frame->saved_regs[PC_REGNUM]
+ = frame->saved_regs[RA_REGNUM];
+ }
+ }
+ }
+}
+
+/* ALPHA stack frames are almost impenetrable. When execution stops,
+ we basically have to look at symbol information for the function
+ that we stopped in, which tells us *which* register (if any) is
+ the base of the frame pointer, and what offset from that register
+ the frame itself is at.
+
+ This presents a problem when trying to examine a stack in memory
+ (that isn't executing at the moment), using the "frame" command. We
+ don't have a PC, nor do we have any registers except SP.
+
+ This routine takes two arguments, SP and PC, and tries to make the
+ cached frames look as if these two arguments defined a frame on the
+ cache. This allows the rest of info frame to extract the important
+ arguments without difficulty. */
+
+struct frame_info *
+setup_arbitrary_frame (argc, argv)
+ int argc;
+ CORE_ADDR *argv;
+{
+ if (argc != 2)
+ error ("ALPHA frame specifications require two arguments: sp and pc");
+
+ return create_new_frame (argv[0], argv[1]);
+}
+
+/* The alpha passes the first six arguments in the registers, the rest on
+ the stack. The register arguments are eventually transferred to the
+ argument transfer area immediately below the stack by the called function
+ anyway. So we `push' at least six arguments on the stack, `reload' the
+ argument registers and then adjust the stack pointer to point past the
+ sixth argument. This algorithm simplifies the passing of a large struct
+ which extends from the registers to the stack.
+ If the called function is returning a structure, the address of the
+ structure to be returned is passed as a hidden first argument. */
+
+CORE_ADDR
+alpha_push_arguments (nargs, args, sp, struct_return, struct_addr)
+ int nargs;
+ value_ptr *args;
+ CORE_ADDR sp;
+ int struct_return;
+ CORE_ADDR struct_addr;
+{
+ register i;
+ int accumulate_size = struct_return ? 8 : 0;
+ int arg_regs_size = ALPHA_NUM_ARG_REGS * 8;
+ struct alpha_arg { char *contents; int len; int offset; };
+ struct alpha_arg *alpha_args =
+ (struct alpha_arg*)alloca (nargs * sizeof (struct alpha_arg));
+ register struct alpha_arg *m_arg;
+ char raw_buffer[sizeof (CORE_ADDR)];
+ int required_arg_regs;
+
+ for (i = 0, m_arg = alpha_args; i < nargs; i++, m_arg++)
+ {
+ value_ptr arg = args[i];
+ struct type *arg_type = check_typedef (VALUE_TYPE (arg));
+ /* Cast argument to long if necessary as the compiler does it too. */
+ switch (TYPE_CODE (arg_type))
+ {
+ case TYPE_CODE_INT:
+ case TYPE_CODE_BOOL:
+ case TYPE_CODE_CHAR:
+ case TYPE_CODE_RANGE:
+ case TYPE_CODE_ENUM:
+ if (TYPE_LENGTH (arg_type) < TYPE_LENGTH (builtin_type_long))
+ {
+ arg_type = builtin_type_long;
+ arg = value_cast (arg_type, arg);
+ }
+ break;
+ default:
+ break;
+ }
+ m_arg->len = TYPE_LENGTH (arg_type);
+ m_arg->offset = accumulate_size;
+ accumulate_size = (accumulate_size + m_arg->len + 7) & ~7;
+ m_arg->contents = VALUE_CONTENTS(arg);
+ }
+
+ /* Determine required argument register loads, loading an argument register
+ is expensive as it uses three ptrace calls. */
+ required_arg_regs = accumulate_size / 8;
+ if (required_arg_regs > ALPHA_NUM_ARG_REGS)
+ required_arg_regs = ALPHA_NUM_ARG_REGS;
+
+ /* Make room for the arguments on the stack. */
+ if (accumulate_size < arg_regs_size)
+ accumulate_size = arg_regs_size;
+ sp -= accumulate_size;
+
+ /* Keep sp aligned to a multiple of 16 as the compiler does it too. */
+ sp &= ~15;
+
+ /* `Push' arguments on the stack. */
+ for (i = nargs; m_arg--, --i >= 0; )
+ write_memory(sp + m_arg->offset, m_arg->contents, m_arg->len);
+ if (struct_return)
+ {
+ store_address (raw_buffer, sizeof (CORE_ADDR), struct_addr);
+ write_memory (sp, raw_buffer, sizeof (CORE_ADDR));
+ }
+
+ /* Load the argument registers. */
+ for (i = 0; i < required_arg_regs; i++)
+ {
+ LONGEST val;
+
+ val = read_memory_integer (sp + i * 8, 8);
+ write_register (A0_REGNUM + i, val);
+ write_register (FPA0_REGNUM + i, val);
+ }
+
+ return sp + arg_regs_size;
+}
+
+void
+alpha_push_dummy_frame()
+{
+ int ireg;
+ struct linked_proc_info *link;
+ alpha_extra_func_info_t proc_desc;
+ CORE_ADDR sp = read_register (SP_REGNUM);
+ CORE_ADDR save_address;
+ char raw_buffer[MAX_REGISTER_RAW_SIZE];
+ unsigned long mask;
+
+ link = (struct linked_proc_info *) xmalloc(sizeof (struct linked_proc_info));
+ link->next = linked_proc_desc_table;
+ linked_proc_desc_table = link;
+
+ proc_desc = &link->info;
+
+ /*
+ * The registers we must save are all those not preserved across
+ * procedure calls.
+ * In addition, we must save the PC and RA.
+ *
+ * Dummy frame layout:
+ * (high memory)
+ * Saved PC
+ * Saved F30
+ * ...
+ * Saved F0
+ * Saved R29
+ * ...
+ * Saved R0
+ * Saved R26 (RA)
+ * Parameter build area
+ * (low memory)
+ */
+
+/* MASK(i,j) == (1<<i) + (1<<(i+1)) + ... + (1<<j)). Assume i<=j<31. */
+#define MASK(i,j) ((((LONGEST)1 << ((j)+1)) - 1) ^ (((LONGEST)1 << (i)) - 1))
+#define GEN_REG_SAVE_MASK (MASK(0,8) | MASK(16,29))
+#define GEN_REG_SAVE_COUNT 24
+#define FLOAT_REG_SAVE_MASK (MASK(0,1) | MASK(10,30))
+#define FLOAT_REG_SAVE_COUNT 23
+ /* The special register is the PC as we have no bit for it in the save masks.
+ alpha_frame_saved_pc knows where the pc is saved in a dummy frame. */
+#define SPECIAL_REG_SAVE_COUNT 1
+
+ PROC_REG_MASK(proc_desc) = GEN_REG_SAVE_MASK;
+ PROC_FREG_MASK(proc_desc) = FLOAT_REG_SAVE_MASK;
+ /* PROC_REG_OFFSET is the offset from the dummy frame to the saved RA,
+ but keep SP aligned to a multiple of 16. */
+ PROC_REG_OFFSET(proc_desc) =
+ - ((8 * (SPECIAL_REG_SAVE_COUNT
+ + GEN_REG_SAVE_COUNT
+ + FLOAT_REG_SAVE_COUNT)
+ + 15) & ~15);
+ PROC_FREG_OFFSET(proc_desc) =
+ PROC_REG_OFFSET(proc_desc) + 8 * GEN_REG_SAVE_COUNT;
+
+ /* Save general registers.
+ The return address register is the first saved register, all other
+ registers follow in ascending order.
+ The PC is saved immediately below the SP. */
+ save_address = sp + PROC_REG_OFFSET(proc_desc);
+ store_address (raw_buffer, 8, read_register (RA_REGNUM));
+ write_memory (save_address, raw_buffer, 8);
+ save_address += 8;
+ mask = PROC_REG_MASK(proc_desc) & 0xffffffffL;
+ for (ireg = 0; mask; ireg++, mask >>= 1)
+ if (mask & 1)
+ {
+ if (ireg == RA_REGNUM)
+ continue;
+ store_address (raw_buffer, 8, read_register (ireg));
+ write_memory (save_address, raw_buffer, 8);
+ save_address += 8;
+ }
+
+ store_address (raw_buffer, 8, read_register (PC_REGNUM));
+ write_memory (sp - 8, raw_buffer, 8);
+
+ /* Save floating point registers. */
+ save_address = sp + PROC_FREG_OFFSET(proc_desc);
+ mask = PROC_FREG_MASK(proc_desc) & 0xffffffffL;
+ for (ireg = 0; mask; ireg++, mask >>= 1)
+ if (mask & 1)
+ {
+ store_address (raw_buffer, 8, read_register (ireg + FP0_REGNUM));
+ write_memory (save_address, raw_buffer, 8);
+ save_address += 8;
+ }
+
+ /* Set and save the frame address for the dummy.
+ This is tricky. The only registers that are suitable for a frame save
+ are those that are preserved across procedure calls (s0-s6). But if
+ a read system call is interrupted and then a dummy call is made
+ (see testsuite/gdb.t17/interrupt.exp) the dummy call hangs till the read
+ is satisfied. Then it returns with the s0-s6 registers set to the values
+ on entry to the read system call and our dummy frame pointer would be
+ destroyed. So we save the dummy frame in the proc_desc and handle the
+ retrieval of the frame pointer of a dummy specifically. The frame register
+ is set to the virtual frame (pseudo) register, it's value will always
+ be read as zero and will help us to catch any errors in the dummy frame
+ retrieval code. */
+ PROC_DUMMY_FRAME(proc_desc) = sp;
+ PROC_FRAME_REG(proc_desc) = FP_REGNUM;
+ PROC_FRAME_OFFSET(proc_desc) = 0;
+ sp += PROC_REG_OFFSET(proc_desc);
+ write_register (SP_REGNUM, sp);
+
+ PROC_LOW_ADDR(proc_desc) = CALL_DUMMY_ADDRESS ();
+ PROC_HIGH_ADDR(proc_desc) = PROC_LOW_ADDR(proc_desc) + 4;
+
+ SET_PROC_DESC_IS_DUMMY(proc_desc);
+ PROC_PC_REG(proc_desc) = RA_REGNUM;
+}
+
+void
+alpha_pop_frame()
+{
+ register int regnum;
+ struct frame_info *frame = get_current_frame ();
+ CORE_ADDR new_sp = frame->frame;
+
+ alpha_extra_func_info_t proc_desc = frame->proc_desc;
+
+ write_register (PC_REGNUM, FRAME_SAVED_PC(frame));
+ if (frame->saved_regs == NULL)
+ alpha_find_saved_regs (frame);
+ if (proc_desc)
+ {
+ for (regnum = 32; --regnum >= 0; )
+ if (PROC_REG_MASK(proc_desc) & (1 << regnum))
+ write_register (regnum,
+ read_memory_integer (frame->saved_regs[regnum],
+ 8));
+ for (regnum = 32; --regnum >= 0; )
+ if (PROC_FREG_MASK(proc_desc) & (1 << regnum))
+ write_register (regnum + FP0_REGNUM,
+ read_memory_integer (frame->saved_regs[regnum + FP0_REGNUM], 8));
+ }
+ write_register (SP_REGNUM, new_sp);
+ flush_cached_frames ();
+
+ if (proc_desc && (PROC_DESC_IS_DUMMY(proc_desc)
+ || PROC_DESC_IS_DYN_SIGTRAMP (proc_desc)))
+ {
+ struct linked_proc_info *pi_ptr, *prev_ptr;
+
+ for (pi_ptr = linked_proc_desc_table, prev_ptr = NULL;
+ pi_ptr != NULL;
+ prev_ptr = pi_ptr, pi_ptr = pi_ptr->next)
+ {
+ if (&pi_ptr->info == proc_desc)
+ break;
+ }
+
+ if (pi_ptr == NULL)
+ error ("Can't locate dummy extra frame info\n");
+
+ if (prev_ptr != NULL)
+ prev_ptr->next = pi_ptr->next;
+ else
+ linked_proc_desc_table = pi_ptr->next;
+
+ free (pi_ptr);
+ }
+}
+
+/* To skip prologues, I use this predicate. Returns either PC itself
+ if the code at PC does not look like a function prologue; otherwise
+ returns an address that (if we're lucky) follows the prologue. If
+ LENIENT, then we must skip everything which is involved in setting
+ up the frame (it's OK to skip more, just so long as we don't skip
+ anything which might clobber the registers which are being saved.
+ Currently we must not skip more on the alpha, but we might the lenient
+ stuff some day. */
+
+CORE_ADDR
+alpha_skip_prologue (pc, lenient)
+ CORE_ADDR pc;
+ int lenient;
+{
+ unsigned long inst;
+ int offset;
+ CORE_ADDR post_prologue_pc;
+ char buf[4];
+
+#ifdef GDB_TARGET_HAS_SHARED_LIBS
+ /* Silently return the unaltered pc upon memory errors.
+ This could happen on OSF/1 if decode_line_1 tries to skip the
+ prologue for quickstarted shared library functions when the
+ shared library is not yet mapped in.
+ Reading target memory is slow over serial lines, so we perform
+ this check only if the target has shared libraries. */
+ if (target_read_memory (pc, buf, 4))
+ return pc;
+#endif
+
+ /* See if we can determine the end of the prologue via the symbol table.
+ If so, then return either PC, or the PC after the prologue, whichever
+ is greater. */
+
+ post_prologue_pc = after_prologue (pc, NULL);
+
+ if (post_prologue_pc != 0)
+ return max (pc, post_prologue_pc);
+
+ /* Can't determine prologue from the symbol table, need to examine
+ instructions. */
+
+ /* Skip the typical prologue instructions. These are the stack adjustment
+ instruction and the instructions that save registers on the stack
+ or in the gcc frame. */
+ for (offset = 0; offset < 100; offset += 4)
+ {
+ int status;
+
+ status = read_memory_nobpt (pc + offset, buf, 4);
+ if (status)
+ memory_error (status, pc + offset);
+ inst = extract_unsigned_integer (buf, 4);
+
+ /* The alpha has no delay slots. But let's keep the lenient stuff,
+ we might need it for something else in the future. */
+ if (lenient && 0)
+ continue;
+
+ if ((inst & 0xffff0000) == 0x27bb0000) /* ldah $gp,n($t12) */
+ continue;
+ if ((inst & 0xffff0000) == 0x23bd0000) /* lda $gp,n($gp) */
+ continue;
+ if ((inst & 0xffff0000) == 0x23de0000) /* lda $sp,n($sp) */
+ continue;
+ else if ((inst & 0xfc1f0000) == 0xb41e0000
+ && (inst & 0xffff0000) != 0xb7fe0000)
+ continue; /* stq reg,n($sp) */
+ /* reg != $zero */
+ else if ((inst & 0xfc1f0000) == 0x9c1e0000
+ && (inst & 0xffff0000) != 0x9ffe0000)
+ continue; /* stt reg,n($sp) */
+ /* reg != $zero */
+ else if (inst == 0x47de040f) /* bis sp,sp,fp */
+ continue;
+ else
+ break;
+ }
+ return pc + offset;
+}
+
+#if 0
+/* Is address PC in the prologue (loosely defined) for function at
+ STARTADDR? */
+
+static int
+alpha_in_lenient_prologue (startaddr, pc)
+ CORE_ADDR startaddr;
+ CORE_ADDR pc;
+{
+ CORE_ADDR end_prologue = alpha_skip_prologue (startaddr, 1);
+ return pc >= startaddr && pc < end_prologue;
+}
+#endif
+
+/* The alpha needs a conversion between register and memory format if
+ the register is a floating point register and
+ memory format is float, as the register format must be double
+ or
+ memory format is an integer with 4 bytes or less, as the representation
+ of integers in floating point registers is different. */
+void
+alpha_register_convert_to_virtual (regnum, valtype, raw_buffer, virtual_buffer)
+ int regnum;
+ struct type *valtype;
+ char *raw_buffer;
+ char *virtual_buffer;
+{
+ if (TYPE_LENGTH (valtype) >= REGISTER_RAW_SIZE (regnum))
+ {
+ memcpy (virtual_buffer, raw_buffer, REGISTER_VIRTUAL_SIZE (regnum));
+ return;
+ }
+
+ if (TYPE_CODE (valtype) == TYPE_CODE_FLT)
+ {
+ double d = extract_floating (raw_buffer, REGISTER_RAW_SIZE (regnum));
+ store_floating (virtual_buffer, TYPE_LENGTH (valtype), d);
+ }
+ else if (TYPE_CODE (valtype) == TYPE_CODE_INT && TYPE_LENGTH (valtype) <= 4)
+ {
+ ULONGEST l;
+ l = extract_unsigned_integer (raw_buffer, REGISTER_RAW_SIZE (regnum));
+ l = ((l >> 32) & 0xc0000000) | ((l >> 29) & 0x3fffffff);
+ store_unsigned_integer (virtual_buffer, TYPE_LENGTH (valtype), l);
+ }
+ else
+ error ("Cannot retrieve value from floating point register");
+}
+
+void
+alpha_register_convert_to_raw (valtype, regnum, virtual_buffer, raw_buffer)
+ struct type *valtype;
+ int regnum;
+ char *virtual_buffer;
+ char *raw_buffer;
+{
+ if (TYPE_LENGTH (valtype) >= REGISTER_RAW_SIZE (regnum))
+ {
+ memcpy (raw_buffer, virtual_buffer, REGISTER_RAW_SIZE (regnum));
+ return;
+ }
+
+ if (TYPE_CODE (valtype) == TYPE_CODE_FLT)
+ {
+ double d = extract_floating (virtual_buffer, TYPE_LENGTH (valtype));
+ store_floating (raw_buffer, REGISTER_RAW_SIZE (regnum), d);
+ }
+ else if (TYPE_CODE (valtype) == TYPE_CODE_INT && TYPE_LENGTH (valtype) <= 4)
+ {
+ ULONGEST l;
+ if (TYPE_UNSIGNED (valtype))
+ l = extract_unsigned_integer (virtual_buffer, TYPE_LENGTH (valtype));
+ else
+ l = extract_signed_integer (virtual_buffer, TYPE_LENGTH (valtype));
+ l = ((l & 0xc0000000) << 32) | ((l & 0x3fffffff) << 29);
+ store_unsigned_integer (raw_buffer, REGISTER_RAW_SIZE (regnum), l);
+ }
+ else
+ error ("Cannot store value in floating point register");
+}
+
+/* Given a return value in `regbuf' with a type `valtype',
+ extract and copy its value into `valbuf'. */
+
+void
+alpha_extract_return_value (valtype, regbuf, valbuf)
+ struct type *valtype;
+ char regbuf[REGISTER_BYTES];
+ char *valbuf;
+{
+ if (TYPE_CODE (valtype) == TYPE_CODE_FLT)
+ alpha_register_convert_to_virtual (FP0_REGNUM, valtype,
+ regbuf + REGISTER_BYTE (FP0_REGNUM),
+ valbuf);
+ else
+ memcpy (valbuf, regbuf + REGISTER_BYTE (V0_REGNUM), TYPE_LENGTH (valtype));
+}
+
+/* Given a return value in `regbuf' with a type `valtype',
+ write its value into the appropriate register. */
+
+void
+alpha_store_return_value (valtype, valbuf)
+ struct type *valtype;
+ char *valbuf;
+{
+ char raw_buffer[MAX_REGISTER_RAW_SIZE];
+ int regnum = V0_REGNUM;
+ int length = TYPE_LENGTH (valtype);
+
+ if (TYPE_CODE (valtype) == TYPE_CODE_FLT)
+ {
+ regnum = FP0_REGNUM;
+ length = REGISTER_RAW_SIZE (regnum);
+ alpha_register_convert_to_raw (valtype, regnum, valbuf, raw_buffer);
+ }
+ else
+ memcpy (raw_buffer, valbuf, length);
+
+ write_register_bytes (REGISTER_BYTE (regnum), raw_buffer, length);
+}
+
+/* Just like reinit_frame_cache, but with the right arguments to be
+ callable as an sfunc. */
+
+static void
+reinit_frame_cache_sfunc (args, from_tty, c)
+ char *args;
+ int from_tty;
+ struct cmd_list_element *c;
+{
+ reinit_frame_cache ();
+}
+
+/* This is the definition of CALL_DUMMY_ADDRESS. It's a heuristic that is used
+ to find a convenient place in the text segment to stick a breakpoint to
+ detect the completion of a target function call (ala call_function_by_hand).
+ */
+
+CORE_ADDR
+alpha_call_dummy_address ()
+{
+ CORE_ADDR entry;
+ struct minimal_symbol *sym;
+
+ entry = entry_point_address ();
+
+ if (entry != 0)
+ return entry;
+
+ sym = lookup_minimal_symbol ("_Prelude", NULL, symfile_objfile);
+
+ if (!sym || MSYMBOL_TYPE (sym) != mst_text)
+ return 0;
+ else
+ return SYMBOL_VALUE_ADDRESS (sym) + 4;
+}
+
+void
+_initialize_alpha_tdep ()
+{
+ struct cmd_list_element *c;
+
+ tm_print_insn = print_insn_alpha;
+
+ /* Let the user set the fence post for heuristic_proc_start. */
+
+ /* We really would like to have both "0" and "unlimited" work, but
+ command.c doesn't deal with that. So make it a var_zinteger
+ because the user can always use "999999" or some such for unlimited. */
+ c = add_set_cmd ("heuristic-fence-post", class_support, var_zinteger,
+ (char *) &heuristic_fence_post,
+ "\
+Set the distance searched for the start of a function.\n\
+If you are debugging a stripped executable, GDB needs to search through the\n\
+program for the start of a function. This command sets the distance of the\n\
+search. The only need to set it is when debugging a stripped executable.",
+ &setlist);
+ /* We need to throw away the frame cache when we set this, since it
+ might change our ability to get backtraces. */
+ c->function.sfunc = reinit_frame_cache_sfunc;
+ add_show_from_set (c, &showlist);
+}