\f
/* 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.
+ the stack. The register arguments are stored in ARG_REG_BUFFER, and
+ then moved into the register file; this simplifies the passing of a
+ large struct which extends from the registers to the stack, plus avoids
+ three ptrace invocations per word.
+
+ We don't bother tracking which register values should go in integer
+ regs or fp regs; we load the same values into both.
+
If the called function is returning a structure, the address of the
structure to be returned is passed as a hidden first argument. */
static CORE_ADDR
-alpha_push_arguments (int nargs, struct value **args, CORE_ADDR sp,
- int struct_return, CORE_ADDR struct_addr)
+alpha_push_dummy_call (struct gdbarch *gdbarch, CORE_ADDR func_addr,
+ struct regcache *regcache, CORE_ADDR bp_addr,
+ int nargs, struct value **args, CORE_ADDR sp,
+ int struct_return, CORE_ADDR struct_addr)
{
int 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));
+ struct alpha_arg *alpha_args
+ = (struct alpha_arg *) alloca (nargs * sizeof (struct alpha_arg));
register struct alpha_arg *m_arg;
- char raw_buffer[ALPHA_REGISTER_BYTES];
+ char arg_reg_buffer[ALPHA_REGISTER_SIZE * ALPHA_NUM_ARG_REGS];
int required_arg_regs;
+ /* The ABI places the address of the called function in T12. */
+ regcache_cooked_write_signed (regcache, ALPHA_T12_REGNUM, func_addr);
+
+ /* Set the return address register to point to the entry point
+ of the program, where a breakpoint lies in wait. */
+ regcache_cooked_write_signed (regcache, ALPHA_RA_REGNUM, bp_addr);
+
+ /* Lay out the arguments in memory. */
for (i = 0, m_arg = alpha_args; i < nargs; i++, m_arg++)
{
struct value *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))
{
arg = value_cast (arg_type, arg);
}
break;
+ case TYPE_CODE_FLT:
+ /* "float" arguments loaded in registers must be passed in
+ register format, aka "double". */
+ if (accumulate_size < sizeof (arg_reg_buffer)
+ && TYPE_LENGTH (arg_type) == 4)
+ {
+ arg_type = builtin_type_double;
+ arg = value_cast (arg_type, arg);
+ }
+ /* Tru64 5.1 has a 128-bit long double, and passes this by
+ invisible reference. No one else uses this data type. */
+ else if (TYPE_LENGTH (arg_type) == 16)
+ {
+ /* Allocate aligned storage. */
+ sp = (sp & -16) - 16;
+
+ /* Write the real data into the stack. */
+ write_memory (sp, VALUE_CONTENTS (arg), 16);
+
+ /* Construct the indirection. */
+ arg_type = lookup_pointer_type (arg_type);
+ arg = value_from_pointer (arg_type, sp);
+ }
+ break;
default:
break;
}
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;
+ if (accumulate_size < sizeof(arg_reg_buffer))
+ accumulate_size = 0;
+ else
+ accumulate_size -= sizeof(arg_reg_buffer);
sp -= accumulate_size;
- /* Keep sp aligned to a multiple of 16 as the compiler does it too. */
+ /* Keep sp aligned to a multiple of 16 as the ABI requires. */
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_unsigned_integer (raw_buffer, ALPHA_REGISTER_BYTES, struct_addr);
- write_memory (sp, raw_buffer, ALPHA_REGISTER_BYTES);
+ char *contents = m_arg->contents;
+ int offset = m_arg->offset;
+ int len = m_arg->len;
+
+ /* Copy the bytes destined for registers into arg_reg_buffer. */
+ if (offset < sizeof(arg_reg_buffer))
+ {
+ if (offset + len <= sizeof(arg_reg_buffer))
+ {
+ memcpy (arg_reg_buffer + offset, contents, len);
+ continue;
+ }
+ else
+ {
+ int tlen = sizeof(arg_reg_buffer) - offset;
+ memcpy (arg_reg_buffer + offset, contents, tlen);
+ offset += tlen;
+ contents += tlen;
+ len -= tlen;
+ }
+ }
+
+ /* Everything else goes to the stack. */
+ write_memory (sp + offset - sizeof(arg_reg_buffer), contents, len);
}
+ if (struct_return)
+ store_unsigned_integer (arg_reg_buffer, ALPHA_REGISTER_SIZE, struct_addr);
/* Load the argument registers. */
for (i = 0; i < required_arg_regs; i++)
{
LONGEST val;
- val = read_memory_integer (sp + i * 8, ALPHA_REGISTER_BYTES);
- write_register (ALPHA_A0_REGNUM + i, val);
- write_register (ALPHA_FPA0_REGNUM + i, val);
+ val = extract_unsigned_integer (arg_reg_buffer + i*ALPHA_REGISTER_SIZE,
+ ALPHA_REGISTER_SIZE);
+ regcache_cooked_write_signed (regcache, ALPHA_A0_REGNUM + i, val);
+ regcache_cooked_write_signed (regcache, ALPHA_FPA0_REGNUM + i, val);
}
- return sp + arg_regs_size;
+ return sp;
}
/* Given a return value in `regbuf' with a type `valtype',
}
\f
-/* Construct an inferior call to FUN. For Alpha this is as simple as
- initializing the RA and T12 registers; everything else is set up by
- generic code. */
-
-static void
-alpha_fix_call_dummy (char *dummy, CORE_ADDR pc, CORE_ADDR fun, int nargs,
- struct value **args, struct type *type, int gcc_p)
-{
- CORE_ADDR bp_address = CALL_DUMMY_ADDRESS ();
-
- if (bp_address == 0)
- error ("no place to put call");
- write_register (ALPHA_RA_REGNUM, bp_address);
- write_register (ALPHA_T12_REGNUM, fun);
-}
-
-/* On the Alpha, the call dummy code is never copied to user space
- (see alpha_fix_call_dummy() above). The contents of this do not
- matter. */
-LONGEST alpha_call_dummy_words[] = { 0 };
-
-\f
/* Figure out where the longjmp will land.
We expect the first arg to be a pointer to the jmp_buf structure from
which we extract the PC (JB_PC) that we will land at. The PC is copied
alpha_extract_struct_value_address);
/* Settings for calling functions in the inferior. */
- set_gdbarch_deprecated_push_arguments (gdbarch, alpha_push_arguments);
- set_gdbarch_deprecated_call_dummy_words (gdbarch, alpha_call_dummy_words);
- set_gdbarch_deprecated_sizeof_call_dummy_words (gdbarch, 0);
- set_gdbarch_deprecated_pc_in_call_dummy (gdbarch, deprecated_pc_in_call_dummy_at_entry_point);
- set_gdbarch_deprecated_fix_call_dummy (gdbarch, alpha_fix_call_dummy);
+ set_gdbarch_push_dummy_call (gdbarch, alpha_push_dummy_call);
/* Methods for saving / extracting a dummy frame's ID. */
set_gdbarch_unwind_dummy_id (gdbarch, alpha_unwind_dummy_id);
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