| /* Target-dependent code for PowerPC systems using the SVR4 ABI |
| for GDB, the GNU debugger. |
| |
| Copyright 2000, 2001, 2002, 2003, 2005 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 "gdbcore.h" |
| #include "inferior.h" |
| #include "regcache.h" |
| #include "value.h" |
| #include "gdb_string.h" |
| #include "gdb_assert.h" |
| #include "ppc-tdep.h" |
| #include "target.h" |
| #include "objfiles.h" |
| #include "infcall.h" |
| |
| /* Pass the arguments in either registers, or in the stack. Using the |
| ppc sysv ABI, the first eight words of the argument list (that might |
| be less than eight parameters if some parameters occupy more than one |
| word) are passed in r3..r10 registers. float and double parameters are |
| passed in fpr's, in addition to that. Rest of the parameters if any |
| are passed in user stack. |
| |
| If the function is returning a structure, then the return address is passed |
| in r3, then the first 7 words of the parametes can be passed in registers, |
| starting from r4. */ |
| |
| CORE_ADDR |
| ppc_sysv_abi_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 (current_gdbarch); |
| const CORE_ADDR saved_sp = read_sp (); |
| int argspace = 0; /* 0 is an initial wrong guess. */ |
| int write_pass; |
| |
| /* Go through the argument list twice. |
| |
| Pass 1: Figure out how much new stack space is required for |
| arguments and pushed values. Unlike the PowerOpen ABI, the SysV |
| ABI doesn't reserve any extra space for parameters which are put |
| in registers, but does always push structures and then pass their |
| address. |
| |
| Pass 2: Replay the same computation but this time also write the |
| values out to the target. */ |
| |
| for (write_pass = 0; write_pass < 2; write_pass++) |
| { |
| int argno; |
| /* Next available floating point register for float and double |
| arguments. */ |
| int freg = 1; |
| /* Next available general register for non-float, non-vector |
| arguments. */ |
| int greg = 3; |
| /* Next available vector register for vector arguments. */ |
| int vreg = 2; |
| /* Arguments start above the "LR save word" and "Back chain". */ |
| int argoffset = 2 * tdep->wordsize; |
| /* Structures start after the arguments. */ |
| int structoffset = argoffset + argspace; |
| |
| /* 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) |
| { |
| if (write_pass) |
| regcache_cooked_write_signed (regcache, |
| tdep->ppc_gp0_regnum + greg, |
| struct_addr); |
| greg++; |
| } |
| |
| for (argno = 0; argno < nargs; argno++) |
| { |
| struct value *arg = args[argno]; |
| struct type *type = check_typedef (value_type (arg)); |
| int len = TYPE_LENGTH (type); |
| const bfd_byte *val = value_contents (arg); |
| |
| if (TYPE_CODE (type) == TYPE_CODE_FLT |
| && ppc_floating_point_unit_p (current_gdbarch) && len <= 8) |
| { |
| /* Floating point value converted to "double" then |
| passed in an FP register, when the registers run out, |
| 8 byte aligned stack is used. */ |
| if (freg <= 8) |
| { |
| if (write_pass) |
| { |
| /* Always store the floating point value using |
| the register's floating-point format. */ |
| gdb_byte regval[MAX_REGISTER_SIZE]; |
| struct type *regtype |
| = register_type (gdbarch, tdep->ppc_fp0_regnum + freg); |
| convert_typed_floating (val, type, regval, regtype); |
| regcache_cooked_write (regcache, |
| tdep->ppc_fp0_regnum + freg, |
| regval); |
| } |
| freg++; |
| } |
| else |
| { |
| /* SysV ABI converts floats to doubles before |
| writing them to an 8 byte aligned stack location. */ |
| argoffset = align_up (argoffset, 8); |
| if (write_pass) |
| { |
| char memval[8]; |
| struct type *memtype; |
| switch (TARGET_BYTE_ORDER) |
| { |
| case BFD_ENDIAN_BIG: |
| memtype = builtin_type_ieee_double_big; |
| break; |
| case BFD_ENDIAN_LITTLE: |
| memtype = builtin_type_ieee_double_little; |
| break; |
| default: |
| internal_error (__FILE__, __LINE__, _("bad switch")); |
| } |
| convert_typed_floating (val, type, memval, memtype); |
| write_memory (sp + argoffset, val, len); |
| } |
| argoffset += 8; |
| } |
| } |
| else if (len == 8 && (TYPE_CODE (type) == TYPE_CODE_INT /* long long */ |
| || (!ppc_floating_point_unit_p (current_gdbarch) && TYPE_CODE (type) == TYPE_CODE_FLT))) /* double */ |
| { |
| /* "long long" or "double" passed in an odd/even |
| register pair with the low addressed word in the odd |
| register and the high addressed word in the even |
| register, or when the registers run out an 8 byte |
| aligned stack location. */ |
| if (greg > 9) |
| { |
| /* Just in case GREG was 10. */ |
| greg = 11; |
| argoffset = align_up (argoffset, 8); |
| if (write_pass) |
| write_memory (sp + argoffset, val, len); |
| argoffset += 8; |
| } |
| else if (tdep->wordsize == 8) |
| { |
| if (write_pass) |
| regcache_cooked_write (regcache, |
| tdep->ppc_gp0_regnum + greg, val); |
| greg += 1; |
| } |
| else |
| { |
| /* Must start on an odd register - r3/r4 etc. */ |
| if ((greg & 1) == 0) |
| greg++; |
| if (write_pass) |
| { |
| regcache_cooked_write (regcache, |
| tdep->ppc_gp0_regnum + greg + 0, |
| val + 0); |
| regcache_cooked_write (regcache, |
| tdep->ppc_gp0_regnum + greg + 1, |
| val + 4); |
| } |
| greg += 2; |
| } |
| } |
| else if (len == 16 |
| && TYPE_CODE (type) == TYPE_CODE_ARRAY |
| && TYPE_VECTOR (type) && tdep->ppc_vr0_regnum >= 0) |
| { |
| /* Vector parameter passed in an Altivec register, or |
| when that runs out, 16 byte aligned stack location. */ |
| if (vreg <= 13) |
| { |
| if (write_pass) |
| regcache_cooked_write (current_regcache, |
| tdep->ppc_vr0_regnum + vreg, val); |
| vreg++; |
| } |
| else |
| { |
| argoffset = align_up (argoffset, 16); |
| if (write_pass) |
| write_memory (sp + argoffset, val, 16); |
| argoffset += 16; |
| } |
| } |
| else if (len == 8 |
| && TYPE_CODE (type) == TYPE_CODE_ARRAY |
| && TYPE_VECTOR (type) && tdep->ppc_ev0_regnum >= 0) |
| { |
| /* Vector parameter passed in an e500 register, or when |
| that runs out, 8 byte aligned stack location. Note |
| that since e500 vector and general purpose registers |
| both map onto the same underlying register set, a |
| "greg" and not a "vreg" is consumed here. A cooked |
| write stores the value in the correct locations |
| within the raw register cache. */ |
| if (greg <= 10) |
| { |
| if (write_pass) |
| regcache_cooked_write (current_regcache, |
| tdep->ppc_ev0_regnum + greg, val); |
| greg++; |
| } |
| else |
| { |
| argoffset = align_up (argoffset, 8); |
| if (write_pass) |
| write_memory (sp + argoffset, val, 8); |
| argoffset += 8; |
| } |
| } |
| else |
| { |
| /* Reduce the parameter down to something that fits in a |
| "word". */ |
| gdb_byte word[MAX_REGISTER_SIZE]; |
| memset (word, 0, MAX_REGISTER_SIZE); |
| if (len > tdep->wordsize |
| || TYPE_CODE (type) == TYPE_CODE_STRUCT |
| || TYPE_CODE (type) == TYPE_CODE_UNION) |
| { |
| /* Structs and large values are put on an 8 byte |
| aligned stack ... */ |
| structoffset = align_up (structoffset, 8); |
| if (write_pass) |
| write_memory (sp + structoffset, val, len); |
| /* ... and then a "word" pointing to that address is |
| passed as the parameter. */ |
| store_unsigned_integer (word, tdep->wordsize, |
| sp + structoffset); |
| structoffset += len; |
| } |
| else if (TYPE_CODE (type) == TYPE_CODE_INT) |
| /* Sign or zero extend the "int" into a "word". */ |
| store_unsigned_integer (word, tdep->wordsize, |
| unpack_long (type, val)); |
| else |
| /* Always goes in the low address. */ |
| memcpy (word, val, len); |
| /* Store that "word" in a register, or on the stack. |
| The words have "4" byte alignment. */ |
| if (greg <= 10) |
| { |
| if (write_pass) |
| regcache_cooked_write (regcache, |
| tdep->ppc_gp0_regnum + greg, word); |
| greg++; |
| } |
| else |
| { |
| argoffset = align_up (argoffset, tdep->wordsize); |
| if (write_pass) |
| write_memory (sp + argoffset, word, tdep->wordsize); |
| argoffset += tdep->wordsize; |
| } |
| } |
| } |
| |
| /* Compute the actual stack space requirements. */ |
| if (!write_pass) |
| { |
| /* Remember the amount of space needed by the arguments. */ |
| argspace = argoffset; |
| /* Allocate space for both the arguments and the structures. */ |
| sp -= (argoffset + structoffset); |
| /* Ensure that the stack is still 16 byte aligned. */ |
| sp = align_down (sp, 16); |
| } |
| } |
| |
| /* Update %sp. */ |
| regcache_cooked_write_signed (regcache, SP_REGNUM, sp); |
| |
| /* Write the backchain (it occupies WORDSIZED bytes). */ |
| write_memory_signed_integer (sp, tdep->wordsize, saved_sp); |
| |
| /* Point the inferior function call's return address at the dummy's |
| breakpoint. */ |
| regcache_cooked_write_signed (regcache, tdep->ppc_lr_regnum, bp_addr); |
| |
| return sp; |
| } |
| |
| /* Handle the return-value conventions specified by the SysV 32-bit |
| PowerPC ABI (including all the supplements): |
| |
| no floating-point: floating-point values returned using 32-bit |
| general-purpose registers. |
| |
| Altivec: 128-bit vectors returned using vector registers. |
| |
| e500: 64-bit vectors returned using the full full 64 bit EV |
| register, floating-point values returned using 32-bit |
| general-purpose registers. |
| |
| GCC (broken): Small struct values right (instead of left) aligned |
| when returned in general-purpose registers. */ |
| |
| static enum return_value_convention |
| do_ppc_sysv_return_value (struct gdbarch *gdbarch, struct type *type, |
| struct regcache *regcache, void *readbuf, |
| const void *writebuf, int broken_gcc) |
| { |
| struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| gdb_assert (tdep->wordsize == 4); |
| if (TYPE_CODE (type) == TYPE_CODE_FLT |
| && TYPE_LENGTH (type) <= 8 |
| && ppc_floating_point_unit_p (gdbarch)) |
| { |
| if (readbuf) |
| { |
| /* Floats and doubles stored in "f1". Convert the value to |
| the required type. */ |
| gdb_byte regval[MAX_REGISTER_SIZE]; |
| struct type *regtype = register_type (gdbarch, |
| tdep->ppc_fp0_regnum + 1); |
| regcache_cooked_read (regcache, tdep->ppc_fp0_regnum + 1, regval); |
| convert_typed_floating (regval, regtype, readbuf, type); |
| } |
| if (writebuf) |
| { |
| /* Floats and doubles stored in "f1". Convert the value to |
| the register's "double" type. */ |
| gdb_byte regval[MAX_REGISTER_SIZE]; |
| struct type *regtype = register_type (gdbarch, tdep->ppc_fp0_regnum); |
| convert_typed_floating (writebuf, type, regval, regtype); |
| regcache_cooked_write (regcache, tdep->ppc_fp0_regnum + 1, regval); |
| } |
| return RETURN_VALUE_REGISTER_CONVENTION; |
| } |
| if ((TYPE_CODE (type) == TYPE_CODE_INT && TYPE_LENGTH (type) == 8) |
| || (TYPE_CODE (type) == TYPE_CODE_FLT && TYPE_LENGTH (type) == 8)) |
| { |
| if (readbuf) |
| { |
| /* A long long, or a double stored in the 32 bit r3/r4. */ |
| regcache_cooked_read (regcache, tdep->ppc_gp0_regnum + 3, |
| (bfd_byte *) readbuf + 0); |
| regcache_cooked_read (regcache, tdep->ppc_gp0_regnum + 4, |
| (bfd_byte *) readbuf + 4); |
| } |
| if (writebuf) |
| { |
| /* A long long, or a double stored in the 32 bit r3/r4. */ |
| regcache_cooked_write (regcache, tdep->ppc_gp0_regnum + 3, |
| (const bfd_byte *) writebuf + 0); |
| regcache_cooked_write (regcache, tdep->ppc_gp0_regnum + 4, |
| (const bfd_byte *) writebuf + 4); |
| } |
| return RETURN_VALUE_REGISTER_CONVENTION; |
| } |
| if (TYPE_CODE (type) == TYPE_CODE_INT |
| && TYPE_LENGTH (type) <= tdep->wordsize) |
| { |
| if (readbuf) |
| { |
| /* Some sort of integer stored in r3. Since TYPE isn't |
| bigger than the register, sign extension isn't a problem |
| - just do everything unsigned. */ |
| ULONGEST regval; |
| regcache_cooked_read_unsigned (regcache, tdep->ppc_gp0_regnum + 3, |
| ®val); |
| store_unsigned_integer (readbuf, TYPE_LENGTH (type), regval); |
| } |
| if (writebuf) |
| { |
| /* Some sort of integer stored in r3. Use unpack_long since |
| that should handle any required sign extension. */ |
| regcache_cooked_write_unsigned (regcache, tdep->ppc_gp0_regnum + 3, |
| unpack_long (type, writebuf)); |
| } |
| return RETURN_VALUE_REGISTER_CONVENTION; |
| } |
| if (TYPE_LENGTH (type) == 16 |
| && TYPE_CODE (type) == TYPE_CODE_ARRAY |
| && TYPE_VECTOR (type) && tdep->ppc_vr0_regnum >= 0) |
| { |
| if (readbuf) |
| { |
| /* Altivec places the return value in "v2". */ |
| regcache_cooked_read (regcache, tdep->ppc_vr0_regnum + 2, readbuf); |
| } |
| if (writebuf) |
| { |
| /* Altivec places the return value in "v2". */ |
| regcache_cooked_write (regcache, tdep->ppc_vr0_regnum + 2, writebuf); |
| } |
| return RETURN_VALUE_REGISTER_CONVENTION; |
| } |
| if (TYPE_LENGTH (type) == 8 |
| && TYPE_CODE (type) == TYPE_CODE_ARRAY |
| && TYPE_VECTOR (type) && tdep->ppc_ev0_regnum >= 0) |
| { |
| /* The e500 ABI places return values for the 64-bit DSP types |
| (__ev64_opaque__) in r3. However, in GDB-speak, ev3 |
| corresponds to the entire r3 value for e500, whereas GDB's r3 |
| only corresponds to the least significant 32-bits. So place |
| the 64-bit DSP type's value in ev3. */ |
| if (readbuf) |
| regcache_cooked_read (regcache, tdep->ppc_ev0_regnum + 3, readbuf); |
| if (writebuf) |
| regcache_cooked_write (regcache, tdep->ppc_ev0_regnum + 3, writebuf); |
| return RETURN_VALUE_REGISTER_CONVENTION; |
| } |
| if (broken_gcc && TYPE_LENGTH (type) <= 8) |
| { |
| if (readbuf) |
| { |
| /* GCC screwed up. The last register isn't "left" aligned. |
| Need to extract the least significant part of each |
| register and then store that. */ |
| /* Transfer any full words. */ |
| int word = 0; |
| while (1) |
| { |
| ULONGEST reg; |
| int len = TYPE_LENGTH (type) - word * tdep->wordsize; |
| if (len <= 0) |
| break; |
| if (len > tdep->wordsize) |
| len = tdep->wordsize; |
| regcache_cooked_read_unsigned (regcache, |
| tdep->ppc_gp0_regnum + 3 + word, |
| ®); |
| store_unsigned_integer (((bfd_byte *) readbuf |
| + word * tdep->wordsize), len, reg); |
| word++; |
| } |
| } |
| if (writebuf) |
| { |
| /* GCC screwed up. The last register isn't "left" aligned. |
| Need to extract the least significant part of each |
| register and then store that. */ |
| /* Transfer any full words. */ |
| int word = 0; |
| while (1) |
| { |
| ULONGEST reg; |
| int len = TYPE_LENGTH (type) - word * tdep->wordsize; |
| if (len <= 0) |
| break; |
| if (len > tdep->wordsize) |
| len = tdep->wordsize; |
| reg = extract_unsigned_integer (((const bfd_byte *) writebuf |
| + word * tdep->wordsize), len); |
| regcache_cooked_write_unsigned (regcache, |
| tdep->ppc_gp0_regnum + 3 + word, |
| reg); |
| word++; |
| } |
| } |
| return RETURN_VALUE_REGISTER_CONVENTION; |
| } |
| if (TYPE_LENGTH (type) <= 8) |
| { |
| if (readbuf) |
| { |
| /* This matches SVr4 PPC, it does not match GCC. */ |
| /* The value is right-padded to 8 bytes and then loaded, as |
| two "words", into r3/r4. */ |
| gdb_byte regvals[MAX_REGISTER_SIZE * 2]; |
| regcache_cooked_read (regcache, tdep->ppc_gp0_regnum + 3, |
| regvals + 0 * tdep->wordsize); |
| if (TYPE_LENGTH (type) > tdep->wordsize) |
| regcache_cooked_read (regcache, tdep->ppc_gp0_regnum + 4, |
| regvals + 1 * tdep->wordsize); |
| memcpy (readbuf, regvals, TYPE_LENGTH (type)); |
| } |
| if (writebuf) |
| { |
| /* This matches SVr4 PPC, it does not match GCC. */ |
| /* The value is padded out to 8 bytes and then loaded, as |
| two "words" into r3/r4. */ |
| gdb_byte regvals[MAX_REGISTER_SIZE * 2]; |
| memset (regvals, 0, sizeof regvals); |
| memcpy (regvals, writebuf, TYPE_LENGTH (type)); |
| regcache_cooked_write (regcache, tdep->ppc_gp0_regnum + 3, |
| regvals + 0 * tdep->wordsize); |
| if (TYPE_LENGTH (type) > tdep->wordsize) |
| regcache_cooked_write (regcache, tdep->ppc_gp0_regnum + 4, |
| regvals + 1 * tdep->wordsize); |
| } |
| return RETURN_VALUE_REGISTER_CONVENTION; |
| } |
| return RETURN_VALUE_STRUCT_CONVENTION; |
| } |
| |
| enum return_value_convention |
| ppc_sysv_abi_return_value (struct gdbarch *gdbarch, struct type *valtype, |
| struct regcache *regcache, gdb_byte *readbuf, |
| const gdb_byte *writebuf) |
| { |
| return do_ppc_sysv_return_value (gdbarch, valtype, regcache, readbuf, |
| writebuf, 0); |
| } |
| |
| enum return_value_convention |
| ppc_sysv_abi_broken_return_value (struct gdbarch *gdbarch, |
| struct type *valtype, |
| struct regcache *regcache, |
| gdb_byte *readbuf, const gdb_byte *writebuf) |
| { |
| return do_ppc_sysv_return_value (gdbarch, valtype, regcache, readbuf, |
| writebuf, 1); |
| } |
| |
| /* The helper function for 64-bit SYSV push_dummy_call. Converts the |
| function's code address back into the function's descriptor |
| address. |
| |
| Find a value for the TOC register. Every symbol should have both |
| ".FN" and "FN" in the minimal symbol table. "FN" points at the |
| FN's descriptor, while ".FN" points at the entry point (which |
| matches FUNC_ADDR). Need to reverse from FUNC_ADDR back to the |
| FN's descriptor address (while at the same time being careful to |
| find "FN" in the same object file as ".FN"). */ |
| |
| static int |
| convert_code_addr_to_desc_addr (CORE_ADDR code_addr, CORE_ADDR *desc_addr) |
| { |
| struct obj_section *dot_fn_section; |
| struct minimal_symbol *dot_fn; |
| struct minimal_symbol *fn; |
| CORE_ADDR toc; |
| /* Find the minimal symbol that corresponds to CODE_ADDR (should |
| have a name of the form ".FN"). */ |
| dot_fn = lookup_minimal_symbol_by_pc (code_addr); |
| if (dot_fn == NULL || SYMBOL_LINKAGE_NAME (dot_fn)[0] != '.') |
| return 0; |
| /* Get the section that contains CODE_ADDR. Need this for the |
| "objfile" that it contains. */ |
| dot_fn_section = find_pc_section (code_addr); |
| if (dot_fn_section == NULL || dot_fn_section->objfile == NULL) |
| return 0; |
| /* Now find the corresponding "FN" (dropping ".") minimal symbol's |
| address. Only look for the minimal symbol in ".FN"'s object file |
| - avoids problems when two object files (i.e., shared libraries) |
| contain a minimal symbol with the same name. */ |
| fn = lookup_minimal_symbol (SYMBOL_LINKAGE_NAME (dot_fn) + 1, NULL, |
| dot_fn_section->objfile); |
| if (fn == NULL) |
| return 0; |
| /* Found a descriptor. */ |
| (*desc_addr) = SYMBOL_VALUE_ADDRESS (fn); |
| return 1; |
| } |
| |
| /* Pass the arguments in either registers, or in the stack. Using the |
| ppc 64 bit SysV ABI. |
| |
| This implements a dumbed down version of the ABI. It always writes |
| values to memory, GPR and FPR, even when not necessary. Doing this |
| greatly simplifies the logic. */ |
| |
| CORE_ADDR |
| ppc64_sysv_abi_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) |
| { |
| CORE_ADDR func_addr = find_function_addr (function, NULL); |
| struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch); |
| /* By this stage in the proceedings, SP has been decremented by "red |
| zone size" + "struct return size". Fetch the stack-pointer from |
| before this and use that as the BACK_CHAIN. */ |
| const CORE_ADDR back_chain = read_sp (); |
| /* See for-loop comment below. */ |
| int write_pass; |
| /* Size of the Altivec's vector parameter region, the final value is |
| computed in the for-loop below. */ |
| LONGEST vparam_size = 0; |
| /* Size of the general parameter region, the final value is computed |
| in the for-loop below. */ |
| LONGEST gparam_size = 0; |
| /* Kevin writes ... I don't mind seeing tdep->wordsize used in the |
| calls to align_up(), align_down(), etc. because this makes it |
| easier to reuse this code (in a copy/paste sense) in the future, |
| but it is a 64-bit ABI and asserting that the wordsize is 8 bytes |
| at some point makes it easier to verify that this function is |
| correct without having to do a non-local analysis to figure out |
| the possible values of tdep->wordsize. */ |
| gdb_assert (tdep->wordsize == 8); |
| |
| /* Go through the argument list twice. |
| |
| Pass 1: Compute the function call's stack space and register |
| requirements. |
| |
| Pass 2: Replay the same computation but this time also write the |
| values out to the target. */ |
| |
| for (write_pass = 0; write_pass < 2; write_pass++) |
| { |
| int argno; |
| /* Next available floating point register for float and double |
| arguments. */ |
| int freg = 1; |
| /* Next available general register for non-vector (but possibly |
| float) arguments. */ |
| int greg = 3; |
| /* Next available vector register for vector arguments. */ |
| int vreg = 2; |
| /* The address, at which the next general purpose parameter |
| (integer, struct, float, ...) should be saved. */ |
| CORE_ADDR gparam; |
| /* Address, at which the next Altivec vector parameter should be |
| saved. */ |
| CORE_ADDR vparam; |
| |
| if (!write_pass) |
| { |
| /* During the first pass, GPARAM and VPARAM are more like |
| offsets (start address zero) than addresses. That way |
| the accumulate the total stack space each region |
| requires. */ |
| gparam = 0; |
| vparam = 0; |
| } |
| else |
| { |
| /* Decrement the stack pointer making space for the Altivec |
| and general on-stack parameters. Set vparam and gparam |
| to their corresponding regions. */ |
| vparam = align_down (sp - vparam_size, 16); |
| gparam = align_down (vparam - gparam_size, 16); |
| /* Add in space for the TOC, link editor double word, |
| compiler double word, LR save area, CR save area. */ |
| sp = align_down (gparam - 48, 16); |
| } |
| |
| /* If the function is returning a `struct', then there is an |
| extra hidden parameter (which will be passed in r3) |
| containing the address of that struct.. In that case we |
| should advance one word and start from r4 register to copy |
| parameters. This also consumes one on-stack parameter slot. */ |
| if (struct_return) |
| { |
| if (write_pass) |
| regcache_cooked_write_signed (regcache, |
| tdep->ppc_gp0_regnum + greg, |
| struct_addr); |
| greg++; |
| gparam = align_up (gparam + tdep->wordsize, tdep->wordsize); |
| } |
| |
| for (argno = 0; argno < nargs; argno++) |
| { |
| struct value *arg = args[argno]; |
| struct type *type = check_typedef (value_type (arg)); |
| const bfd_byte *val = value_contents (arg); |
| if (TYPE_CODE (type) == TYPE_CODE_FLT && TYPE_LENGTH (type) <= 8) |
| { |
| /* Floats and Doubles go in f1 .. f13. They also |
| consume a left aligned GREG,, and can end up in |
| memory. */ |
| if (write_pass) |
| { |
| if (ppc_floating_point_unit_p (current_gdbarch) |
| && freg <= 13) |
| { |
| gdb_byte regval[MAX_REGISTER_SIZE]; |
| struct type *regtype |
| = register_type (gdbarch, tdep->ppc_fp0_regnum); |
| convert_typed_floating (val, type, regval, regtype); |
| regcache_cooked_write (regcache, |
| tdep->ppc_fp0_regnum + freg, |
| regval); |
| } |
| if (greg <= 10) |
| { |
| /* The ABI states "Single precision floating |
| point values are mapped to the first word in |
| a single doubleword" and "... floating point |
| values mapped to the first eight doublewords |
| of the parameter save area are also passed in |
| general registers"). |
| |
| This code interprets that to mean: store it, |
| left aligned, in the general register. */ |
| gdb_byte regval[MAX_REGISTER_SIZE]; |
| memset (regval, 0, sizeof regval); |
| memcpy (regval, val, TYPE_LENGTH (type)); |
| regcache_cooked_write (regcache, |
| tdep->ppc_gp0_regnum + greg, |
| regval); |
| } |
| write_memory (gparam, val, TYPE_LENGTH (type)); |
| } |
| /* Always consume parameter stack space. */ |
| freg++; |
| greg++; |
| gparam = align_up (gparam + TYPE_LENGTH (type), tdep->wordsize); |
| } |
| else if (TYPE_LENGTH (type) == 16 && TYPE_VECTOR (type) |
| && TYPE_CODE (type) == TYPE_CODE_ARRAY |
| && tdep->ppc_vr0_regnum >= 0) |
| { |
| /* In the Altivec ABI, vectors go in the vector |
| registers v2 .. v13, or when that runs out, a vector |
| annex which goes above all the normal parameters. |
| NOTE: cagney/2003-09-21: This is a guess based on the |
| PowerOpen Altivec ABI. */ |
| if (vreg <= 13) |
| { |
| if (write_pass) |
| regcache_cooked_write (regcache, |
| tdep->ppc_vr0_regnum + vreg, val); |
| vreg++; |
| } |
| else |
| { |
| if (write_pass) |
| write_memory (vparam, val, TYPE_LENGTH (type)); |
| vparam = align_up (vparam + TYPE_LENGTH (type), 16); |
| } |
| } |
| else if ((TYPE_CODE (type) == TYPE_CODE_INT |
| || TYPE_CODE (type) == TYPE_CODE_ENUM |
| || TYPE_CODE (type) == TYPE_CODE_PTR) |
| && TYPE_LENGTH (type) <= 8) |
| { |
| /* Scalars and Pointers get sign[un]extended and go in |
| gpr3 .. gpr10. They can also end up in memory. */ |
| if (write_pass) |
| { |
| /* Sign extend the value, then store it unsigned. */ |
| ULONGEST word = unpack_long (type, val); |
| /* Convert any function code addresses into |
| descriptors. */ |
| if (TYPE_CODE (type) == TYPE_CODE_PTR |
| && TYPE_CODE (TYPE_TARGET_TYPE (type)) == TYPE_CODE_FUNC) |
| { |
| CORE_ADDR desc = word; |
| convert_code_addr_to_desc_addr (word, &desc); |
| word = desc; |
| } |
| if (greg <= 10) |
| regcache_cooked_write_unsigned (regcache, |
| tdep->ppc_gp0_regnum + |
| greg, word); |
| write_memory_unsigned_integer (gparam, tdep->wordsize, |
| word); |
| } |
| greg++; |
| gparam = align_up (gparam + TYPE_LENGTH (type), tdep->wordsize); |
| } |
| else |
| { |
| int byte; |
| for (byte = 0; byte < TYPE_LENGTH (type); |
| byte += tdep->wordsize) |
| { |
| if (write_pass && greg <= 10) |
| { |
| gdb_byte regval[MAX_REGISTER_SIZE]; |
| int len = TYPE_LENGTH (type) - byte; |
| if (len > tdep->wordsize) |
| len = tdep->wordsize; |
| memset (regval, 0, sizeof regval); |
| /* WARNING: cagney/2003-09-21: As best I can |
| tell, the ABI specifies that the value should |
| be left aligned. Unfortunately, GCC doesn't |
| do this - it instead right aligns even sized |
| values and puts odd sized values on the |
| stack. Work around that by putting both a |
| left and right aligned value into the |
| register (hopefully no one notices :-^). |
| Arrrgh! */ |
| /* Left aligned (8 byte values such as pointers |
| fill the buffer). */ |
| memcpy (regval, val + byte, len); |
| /* Right aligned (but only if even). */ |
| if (len == 1 || len == 2 || len == 4) |
| memcpy (regval + tdep->wordsize - len, |
| val + byte, len); |
| regcache_cooked_write (regcache, greg, regval); |
| } |
| greg++; |
| } |
| if (write_pass) |
| /* WARNING: cagney/2003-09-21: Strictly speaking, this |
| isn't necessary, unfortunately, GCC appears to get |
| "struct convention" parameter passing wrong putting |
| odd sized structures in memory instead of in a |
| register. Work around this by always writing the |
| value to memory. Fortunately, doing this |
| simplifies the code. */ |
| write_memory (gparam, val, TYPE_LENGTH (type)); |
| if (write_pass) |
| /* WARNING: cagney/2004-06-20: It appears that GCC |
| likes to put structures containing a single |
| floating-point member in an FP register instead of |
| general general purpose. */ |
| /* Always consume parameter stack space. */ |
| gparam = align_up (gparam + TYPE_LENGTH (type), tdep->wordsize); |
| } |
| } |
| |
| if (!write_pass) |
| { |
| /* Save the true region sizes ready for the second pass. */ |
| vparam_size = vparam; |
| /* Make certain that the general parameter save area is at |
| least the minimum 8 registers (or doublewords) in size. */ |
| if (greg < 8) |
| gparam_size = 8 * tdep->wordsize; |
| else |
| gparam_size = gparam; |
| } |
| } |
| |
| /* Update %sp. */ |
| regcache_cooked_write_signed (regcache, SP_REGNUM, sp); |
| |
| /* Write the backchain (it occupies WORDSIZED bytes). */ |
| write_memory_signed_integer (sp, tdep->wordsize, back_chain); |
| |
| /* Point the inferior function call's return address at the dummy's |
| breakpoint. */ |
| regcache_cooked_write_signed (regcache, tdep->ppc_lr_regnum, bp_addr); |
| |
| /* Use the func_addr to find the descriptor, and use that to find |
| the TOC. */ |
| { |
| CORE_ADDR desc_addr; |
| if (convert_code_addr_to_desc_addr (func_addr, &desc_addr)) |
| { |
| /* The TOC is the second double word in the descriptor. */ |
| CORE_ADDR toc = |
| read_memory_unsigned_integer (desc_addr + tdep->wordsize, |
| tdep->wordsize); |
| regcache_cooked_write_unsigned (regcache, |
| tdep->ppc_gp0_regnum + 2, toc); |
| } |
| } |
| |
| return sp; |
| } |
| |
| |
| /* The 64 bit ABI retun value convention. |
| |
| Return non-zero if the return-value is stored in a register, return |
| 0 if the return-value is instead stored on the stack (a.k.a., |
| struct return convention). |
| |
| For a return-value stored in a register: when WRITEBUF is non-NULL, |
| copy the buffer to the corresponding register return-value location |
| location; when READBUF is non-NULL, fill the buffer from the |
| corresponding register return-value location. */ |
| enum return_value_convention |
| ppc64_sysv_abi_return_value (struct gdbarch *gdbarch, struct type *valtype, |
| struct regcache *regcache, gdb_byte *readbuf, |
| const gdb_byte *writebuf) |
| { |
| struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| |
| /* This function exists to support a calling convention that |
| requires floating-point registers. It shouldn't be used on |
| processors that lack them. */ |
| gdb_assert (ppc_floating_point_unit_p (gdbarch)); |
| |
| /* Floats and doubles in F1. */ |
| if (TYPE_CODE (valtype) == TYPE_CODE_FLT && TYPE_LENGTH (valtype) <= 8) |
| { |
| gdb_byte regval[MAX_REGISTER_SIZE]; |
| struct type *regtype = register_type (gdbarch, tdep->ppc_fp0_regnum); |
| if (writebuf != NULL) |
| { |
| convert_typed_floating (writebuf, valtype, regval, regtype); |
| regcache_cooked_write (regcache, tdep->ppc_fp0_regnum + 1, regval); |
| } |
| if (readbuf != NULL) |
| { |
| regcache_cooked_read (regcache, tdep->ppc_fp0_regnum + 1, regval); |
| convert_typed_floating (regval, regtype, readbuf, valtype); |
| } |
| return RETURN_VALUE_REGISTER_CONVENTION; |
| } |
| if ((TYPE_CODE (valtype) == TYPE_CODE_INT |
| || TYPE_CODE (valtype) == TYPE_CODE_ENUM) |
| && TYPE_LENGTH (valtype) <= 8) |
| { |
| /* Integers in r3. */ |
| if (writebuf != NULL) |
| { |
| /* Be careful to sign extend the value. */ |
| regcache_cooked_write_unsigned (regcache, tdep->ppc_gp0_regnum + 3, |
| unpack_long (valtype, writebuf)); |
| } |
| if (readbuf != NULL) |
| { |
| /* Extract the integer from r3. Since this is truncating the |
| value, there isn't a sign extension problem. */ |
| ULONGEST regval; |
| regcache_cooked_read_unsigned (regcache, tdep->ppc_gp0_regnum + 3, |
| ®val); |
| store_unsigned_integer (readbuf, TYPE_LENGTH (valtype), regval); |
| } |
| return RETURN_VALUE_REGISTER_CONVENTION; |
| } |
| /* All pointers live in r3. */ |
| if (TYPE_CODE (valtype) == TYPE_CODE_PTR) |
| { |
| /* All pointers live in r3. */ |
| if (writebuf != NULL) |
| regcache_cooked_write (regcache, tdep->ppc_gp0_regnum + 3, writebuf); |
| if (readbuf != NULL) |
| regcache_cooked_read (regcache, tdep->ppc_gp0_regnum + 3, readbuf); |
| return RETURN_VALUE_REGISTER_CONVENTION; |
| } |
| if (TYPE_CODE (valtype) == TYPE_CODE_ARRAY |
| && TYPE_LENGTH (valtype) <= 8 |
| && TYPE_CODE (TYPE_TARGET_TYPE (valtype)) == TYPE_CODE_INT |
| && TYPE_LENGTH (TYPE_TARGET_TYPE (valtype)) == 1) |
| { |
| /* Small character arrays are returned, right justified, in r3. */ |
| int offset = (register_size (gdbarch, tdep->ppc_gp0_regnum + 3) |
| - TYPE_LENGTH (valtype)); |
| if (writebuf != NULL) |
| regcache_cooked_write_part (regcache, tdep->ppc_gp0_regnum + 3, |
| offset, TYPE_LENGTH (valtype), writebuf); |
| if (readbuf != NULL) |
| regcache_cooked_read_part (regcache, tdep->ppc_gp0_regnum + 3, |
| offset, TYPE_LENGTH (valtype), readbuf); |
| return RETURN_VALUE_REGISTER_CONVENTION; |
| } |
| /* Big floating point values get stored in adjacent floating |
| point registers. */ |
| if (TYPE_CODE (valtype) == TYPE_CODE_FLT |
| && (TYPE_LENGTH (valtype) == 16 || TYPE_LENGTH (valtype) == 32)) |
| { |
| if (writebuf || readbuf != NULL) |
| { |
| int i; |
| for (i = 0; i < TYPE_LENGTH (valtype) / 8; i++) |
| { |
| if (writebuf != NULL) |
| regcache_cooked_write (regcache, tdep->ppc_fp0_regnum + 1 + i, |
| (const bfd_byte *) writebuf + i * 8); |
| if (readbuf != NULL) |
| regcache_cooked_read (regcache, tdep->ppc_fp0_regnum + 1 + i, |
| (bfd_byte *) readbuf + i * 8); |
| } |
| } |
| return RETURN_VALUE_REGISTER_CONVENTION; |
| } |
| /* Complex values get returned in f1:f2, need to convert. */ |
| if (TYPE_CODE (valtype) == TYPE_CODE_COMPLEX |
| && (TYPE_LENGTH (valtype) == 8 || TYPE_LENGTH (valtype) == 16)) |
| { |
| if (regcache != NULL) |
| { |
| int i; |
| for (i = 0; i < 2; i++) |
| { |
| gdb_byte regval[MAX_REGISTER_SIZE]; |
| struct type *regtype = |
| register_type (current_gdbarch, tdep->ppc_fp0_regnum); |
| if (writebuf != NULL) |
| { |
| convert_typed_floating ((const bfd_byte *) writebuf + |
| i * (TYPE_LENGTH (valtype) / 2), |
| valtype, regval, regtype); |
| regcache_cooked_write (regcache, |
| tdep->ppc_fp0_regnum + 1 + i, |
| regval); |
| } |
| if (readbuf != NULL) |
| { |
| regcache_cooked_read (regcache, |
| tdep->ppc_fp0_regnum + 1 + i, |
| regval); |
| convert_typed_floating (regval, regtype, |
| (bfd_byte *) readbuf + |
| i * (TYPE_LENGTH (valtype) / 2), |
| valtype); |
| } |
| } |
| } |
| return RETURN_VALUE_REGISTER_CONVENTION; |
| } |
| /* Big complex values get stored in f1:f4. */ |
| if (TYPE_CODE (valtype) == TYPE_CODE_COMPLEX && TYPE_LENGTH (valtype) == 32) |
| { |
| if (regcache != NULL) |
| { |
| int i; |
| for (i = 0; i < 4; i++) |
| { |
| if (writebuf != NULL) |
| regcache_cooked_write (regcache, tdep->ppc_fp0_regnum + 1 + i, |
| (const bfd_byte *) writebuf + i * 8); |
| if (readbuf != NULL) |
| regcache_cooked_read (regcache, tdep->ppc_fp0_regnum + 1 + i, |
| (bfd_byte *) readbuf + i * 8); |
| } |
| } |
| return RETURN_VALUE_REGISTER_CONVENTION; |
| } |
| return RETURN_VALUE_STRUCT_CONVENTION; |
| } |
| |
| CORE_ADDR |
| ppc64_sysv_abi_adjust_breakpoint_address (struct gdbarch *gdbarch, |
| CORE_ADDR bpaddr) |
| { |
| /* PPC64 SYSV specifies that the minimal-symbol "FN" should point at |
| a function-descriptor while the corresponding minimal-symbol |
| ".FN" should point at the entry point. Consequently, a command |
| like "break FN" applied to an object file with only minimal |
| symbols, will insert the breakpoint into the descriptor at "FN" |
| and not the function at ".FN". Avoid this confusion by adjusting |
| any attempt to set a descriptor breakpoint into a corresponding |
| function breakpoint. Note that GDB warns the user when this |
| adjustment is applied - that's ok as otherwise the user will have |
| no way of knowing why their breakpoint at "FN" resulted in the |
| program stopping at ".FN". */ |
| return gdbarch_convert_from_func_ptr_addr (gdbarch, bpaddr, ¤t_target); |
| } |