--- /dev/null
+/* Copyright (C) 2012 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 3 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, see <http://www.gnu.org/licenses/>. */
+
+#include "defs.h"
+#include "osabi.h"
+#include "regcache.h"
+#include "gdbcore.h"
+#include "gdbtypes.h"
+#include "infcall.h"
+#include "ppc-tdep.h"
+#include "value.h"
+#include "xcoffread.h"
+
+/* Implement the "push_dummy_call" gdbarch method. */
+
+static CORE_ADDR
+rs6000_lynx178_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)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ int ii;
+ int len = 0;
+ int argno; /* current argument number */
+ int argbytes; /* current argument byte */
+ gdb_byte tmp_buffer[50];
+ int f_argno = 0; /* current floating point argno */
+ int wordsize = gdbarch_tdep (gdbarch)->wordsize;
+ CORE_ADDR func_addr = find_function_addr (function, NULL);
+
+ struct value *arg = 0;
+ struct type *type;
+
+ ULONGEST saved_sp;
+
+ /* The calling convention this function implements assumes the
+ processor has floating-point registers. We shouldn't be using it
+ on PPC variants that lack them. */
+ gdb_assert (ppc_floating_point_unit_p (gdbarch));
+
+ /* The first eight words of ther arguments are passed in registers.
+ Copy them appropriately. */
+ ii = 0;
+
+ /* If the function is returning a `struct', then the first word
+ (which will be passed in r3) is used for struct return address.
+ In that case we should advance one word and start from r4
+ register to copy parameters. */
+ if (struct_return)
+ {
+ regcache_raw_write_unsigned (regcache, tdep->ppc_gp0_regnum + 3,
+ struct_addr);
+ ii++;
+ }
+
+ /* Effectively indirect call... gcc does...
+
+ return_val example( float, int);
+
+ eabi:
+ float in fp0, int in r3
+ offset of stack on overflow 8/16
+ for varargs, must go by type.
+ power open:
+ float in r3&r4, int in r5
+ offset of stack on overflow different
+ both:
+ return in r3 or f0. If no float, must study how gcc emulates floats;
+ pay attention to arg promotion.
+ User may have to cast\args to handle promotion correctly
+ since gdb won't know if prototype supplied or not. */
+
+ for (argno = 0, argbytes = 0; argno < nargs && ii < 8; ++ii)
+ {
+ int reg_size = register_size (gdbarch, ii + 3);
+
+ arg = args[argno];
+ type = check_typedef (value_type (arg));
+ len = TYPE_LENGTH (type);
+
+ if (TYPE_CODE (type) == TYPE_CODE_FLT)
+ {
+
+ /* Floating point arguments are passed in fpr's, as well as gpr's.
+ There are 13 fpr's reserved for passing parameters. At this point
+ there is no way we would run out of them. */
+
+ gdb_assert (len <= 8);
+
+ regcache_cooked_write (regcache,
+ tdep->ppc_fp0_regnum + 1 + f_argno,
+ value_contents (arg));
+ ++f_argno;
+ }
+
+ if (len > reg_size)
+ {
+
+ /* Argument takes more than one register. */
+ while (argbytes < len)
+ {
+ gdb_byte word[MAX_REGISTER_SIZE];
+ memset (word, 0, reg_size);
+ memcpy (word,
+ ((char *) value_contents (arg)) + argbytes,
+ (len - argbytes) > reg_size
+ ? reg_size : len - argbytes);
+ regcache_cooked_write (regcache,
+ tdep->ppc_gp0_regnum + 3 + ii,
+ word);
+ ++ii, argbytes += reg_size;
+
+ if (ii >= 8)
+ goto ran_out_of_registers_for_arguments;
+ }
+ argbytes = 0;
+ --ii;
+ }
+ else
+ {
+ /* Argument can fit in one register. No problem. */
+ int adj = gdbarch_byte_order (gdbarch)
+ == BFD_ENDIAN_BIG ? reg_size - len : 0;
+ gdb_byte word[MAX_REGISTER_SIZE];
+
+ memset (word, 0, reg_size);
+ memcpy (word, value_contents (arg), len);
+ regcache_cooked_write (regcache, tdep->ppc_gp0_regnum + 3 +ii, word);
+ }
+ ++argno;
+ }
+
+ran_out_of_registers_for_arguments:
+
+ regcache_cooked_read_unsigned (regcache,
+ gdbarch_sp_regnum (gdbarch),
+ &saved_sp);
+
+ /* Location for 8 parameters are always reserved. */
+ sp -= wordsize * 8;
+
+ /* Another six words for back chain, TOC register, link register, etc. */
+ sp -= wordsize * 6;
+
+ /* Stack pointer must be quadword aligned. */
+ sp = align_down (sp, 16);
+
+ /* If there are more arguments, allocate space for them in
+ the stack, then push them starting from the ninth one. */
+
+ if ((argno < nargs) || argbytes)
+ {
+ int space = 0, jj;
+
+ if (argbytes)
+ {
+ space += align_up (len - argbytes, 4);
+ jj = argno + 1;
+ }
+ else
+ jj = argno;
+
+ for (; jj < nargs; ++jj)
+ {
+ struct value *val = args[jj];
+
+ space += align_up (TYPE_LENGTH (value_type (val)), 4);
+ }
+
+ /* Add location required for the rest of the parameters. */
+ space = align_up (space, 16);
+ sp -= space;
+
+ /* This is another instance we need to be concerned about
+ securing our stack space. If we write anything underneath %sp
+ (r1), we might conflict with the kernel who thinks he is free
+ to use this area. So, update %sp first before doing anything
+ else. */
+
+ regcache_raw_write_signed (regcache,
+ gdbarch_sp_regnum (gdbarch), sp);
+
+ /* If the last argument copied into the registers didn't fit there
+ completely, push the rest of it into stack. */
+
+ if (argbytes)
+ {
+ write_memory (sp + 24 + (ii * 4),
+ value_contents (arg) + argbytes,
+ len - argbytes);
+ ++argno;
+ ii += align_up (len - argbytes, 4) / 4;
+ }
+
+ /* Push the rest of the arguments into stack. */
+ for (; argno < nargs; ++argno)
+ {
+
+ arg = args[argno];
+ type = check_typedef (value_type (arg));
+ len = TYPE_LENGTH (type);
+
+
+ /* Float types should be passed in fpr's, as well as in the
+ stack. */
+ if (TYPE_CODE (type) == TYPE_CODE_FLT && f_argno < 13)
+ {
+
+ gdb_assert (len <= 8);
+
+ regcache_cooked_write (regcache,
+ tdep->ppc_fp0_regnum + 1 + f_argno,
+ value_contents (arg));
+ ++f_argno;
+ }
+
+ write_memory (sp + 24 + (ii * 4), value_contents (arg), len);
+ ii += align_up (len, 4) / 4;
+ }
+ }
+
+ /* Set the stack pointer. According to the ABI, the SP is meant to
+ be set _before_ the corresponding stack space is used. On AIX,
+ this even applies when the target has been completely stopped!
+ Not doing this can lead to conflicts with the kernel which thinks
+ that it still has control over this not-yet-allocated stack
+ region. */
+ regcache_raw_write_signed (regcache, gdbarch_sp_regnum (gdbarch), sp);
+
+ /* Set back chain properly. */
+ store_unsigned_integer (tmp_buffer, wordsize, byte_order, saved_sp);
+ write_memory (sp, tmp_buffer, wordsize);
+
+ /* Point the inferior function call's return address at the dummy's
+ breakpoint. */
+ regcache_raw_write_signed (regcache, tdep->ppc_lr_regnum, bp_addr);
+
+ target_store_registers (regcache, -1);
+ return sp;
+}
+
+/* Implement the "return_value" gdbarch method. */
+
+static enum return_value_convention
+rs6000_lynx178_return_value (struct gdbarch *gdbarch, struct value *function,
+ struct type *valtype, struct regcache *regcache,
+ gdb_byte *readbuf, const gdb_byte *writebuf)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+
+ /* The calling convention this function implements assumes the
+ processor has floating-point registers. We shouldn't be using it
+ on PowerPC variants that lack them. */
+ gdb_assert (ppc_floating_point_unit_p (gdbarch));
+
+ /* AltiVec extension: Functions that declare a vector data type as a
+ return value place that return value in VR2. */
+ if (TYPE_CODE (valtype) == TYPE_CODE_ARRAY && TYPE_VECTOR (valtype)
+ && TYPE_LENGTH (valtype) == 16)
+ {
+ if (readbuf)
+ regcache_cooked_read (regcache, tdep->ppc_vr0_regnum + 2, readbuf);
+ if (writebuf)
+ regcache_cooked_write (regcache, tdep->ppc_vr0_regnum + 2, writebuf);
+
+ return RETURN_VALUE_REGISTER_CONVENTION;
+ }
+
+ /* If the called subprogram returns an aggregate, there exists an
+ implicit first argument, whose value is the address of a caller-
+ allocated buffer into which the callee is assumed to store its
+ return value. All explicit parameters are appropriately
+ relabeled. */
+ if (TYPE_CODE (valtype) == TYPE_CODE_STRUCT
+ || TYPE_CODE (valtype) == TYPE_CODE_UNION
+ || TYPE_CODE (valtype) == TYPE_CODE_ARRAY)
+ return RETURN_VALUE_STRUCT_CONVENTION;
+
+ /* Scalar floating-point values are returned in FPR1 for float or
+ double, and in FPR1:FPR2 for quadword precision. Fortran
+ complex*8 and complex*16 are returned in FPR1:FPR2, and
+ complex*32 is returned in FPR1:FPR4. */
+ if (TYPE_CODE (valtype) == TYPE_CODE_FLT
+ && (TYPE_LENGTH (valtype) == 4 || TYPE_LENGTH (valtype) == 8))
+ {
+ struct type *regtype = register_type (gdbarch, tdep->ppc_fp0_regnum);
+ gdb_byte regval[8];
+
+ /* FIXME: kettenis/2007-01-01: Add support for quadword
+ precision and complex. */
+
+ if (readbuf)
+ {
+ regcache_cooked_read (regcache, tdep->ppc_fp0_regnum + 1, regval);
+ convert_typed_floating (regval, regtype, readbuf, valtype);
+ }
+ if (writebuf)
+ {
+ convert_typed_floating (writebuf, valtype, regval, regtype);
+ regcache_cooked_write (regcache, tdep->ppc_fp0_regnum + 1, regval);
+ }
+
+ return RETURN_VALUE_REGISTER_CONVENTION;
+ }
+
+ /* Values of the types int, long, short, pointer, and char (length
+ is less than or equal to four bytes), as well as bit values of
+ lengths less than or equal to 32 bits, must be returned right
+ justified in GPR3 with signed values sign extended and unsigned
+ values zero extended, as necessary. */
+ if (TYPE_LENGTH (valtype) <= tdep->wordsize)
+ {
+ if (readbuf)
+ {
+ ULONGEST regval;
+
+ /* For reading we don't have to worry about sign extension. */
+ regcache_cooked_read_unsigned (regcache, tdep->ppc_gp0_regnum + 3,
+ ®val);
+ store_unsigned_integer (readbuf, TYPE_LENGTH (valtype), byte_order,
+ regval);
+ }
+ if (writebuf)
+ {
+ /* For writing, use unpack_long since that should handle any
+ required sign extension. */
+ regcache_cooked_write_unsigned (regcache, tdep->ppc_gp0_regnum + 3,
+ unpack_long (valtype, writebuf));
+ }
+
+ return RETURN_VALUE_REGISTER_CONVENTION;
+ }
+
+ /* Eight-byte non-floating-point scalar values must be returned in
+ GPR3:GPR4. */
+
+ if (TYPE_LENGTH (valtype) == 8)
+ {
+ gdb_assert (TYPE_CODE (valtype) != TYPE_CODE_FLT);
+ gdb_assert (tdep->wordsize == 4);
+
+ if (readbuf)
+ {
+ gdb_byte regval[8];
+
+ regcache_cooked_read (regcache, tdep->ppc_gp0_regnum + 3, regval);
+ regcache_cooked_read (regcache, tdep->ppc_gp0_regnum + 4,
+ regval + 4);
+ memcpy (readbuf, regval, 8);
+ }
+ if (writebuf)
+ {
+ regcache_cooked_write (regcache, tdep->ppc_gp0_regnum + 3, writebuf);
+ regcache_cooked_write (regcache, tdep->ppc_gp0_regnum + 4,
+ writebuf + 4);
+ }
+
+ return RETURN_VALUE_REGISTER_CONVENTION;
+ }
+
+ return RETURN_VALUE_STRUCT_CONVENTION;
+}
+
+/* PowerPC Lynx178 OSABI sniffer. */
+
+static enum gdb_osabi
+rs6000_lynx178_osabi_sniffer (bfd *abfd)
+{
+ if (bfd_get_flavour (abfd) != bfd_target_xcoff_flavour)
+ return GDB_OSABI_UNKNOWN;
+
+ /* The only noticeable difference between Lynx178 XCOFF files and
+ AIX XCOFF files comes from the fact that there are no shared
+ libraries on Lynx178. So if the number of import files is
+ different from zero, it cannot be a Lynx178 binary. */
+ if (xcoff_get_n_import_files (abfd) != 0)
+ return GDB_OSABI_UNKNOWN;
+
+ return GDB_OSABI_LYNXOS178;
+}
+
+/* Callback for powerpc-lynx178 initialization. */
+
+static void
+rs6000_lynx178_init_osabi (struct gdbarch_info info, struct gdbarch *gdbarch)
+{
+ set_gdbarch_push_dummy_call (gdbarch, rs6000_lynx178_push_dummy_call);
+ set_gdbarch_return_value (gdbarch, rs6000_lynx178_return_value);
+ set_gdbarch_long_double_bit (gdbarch, 8 * TARGET_CHAR_BIT);
+}
+
+/* -Wmissing-prototypes. */
+extern initialize_file_ftype _initialize_rs6000_lynx178_tdep;
+
+void
+_initialize_rs6000_lynx178_tdep (void)
+{
+ gdbarch_register_osabi_sniffer (bfd_arch_rs6000,
+ bfd_target_xcoff_flavour,
+ rs6000_lynx178_osabi_sniffer);
+ gdbarch_register_osabi (bfd_arch_rs6000, 0, GDB_OSABI_LYNXOS178,
+ rs6000_lynx178_init_osabi);
+}
+
projects / binutils-gdb.git / commitdiff