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Diffstat (limited to 'backends/ia64_retval.c')
| -rw-r--r-- | backends/ia64_retval.c | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/backends/ia64_retval.c b/backends/ia64_retval.c new file mode 100644 index 00000000..b66fe5c2 --- /dev/null +++ b/backends/ia64_retval.c @@ -0,0 +1,223 @@ +/* Function return value location for IA64 ABI. + Copyright (C) 2006 Red Hat, Inc. + This file is part of Red Hat elfutils. + + Red Hat elfutils 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; version 2 of the License. + + Red Hat elfutils 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 Red Hat elfutils; if not, write to the Free Software Foundation, + Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA. + + Red Hat elfutils is an included package of the Open Invention Network. + An included package of the Open Invention Network is a package for which + Open Invention Network licensees cross-license their patents. No patent + license is granted, either expressly or impliedly, by designation as an + included package. Should you wish to participate in the Open Invention + Network licensing program, please visit www.openinventionnetwork.com + <http://www.openinventionnetwork.com>. */ + +#ifdef HAVE_CONFIG_H +# include <config.h> +#endif + +#include <assert.h> +#include <dwarf.h> + +#define BACKEND ia64_ +#include "libebl_CPU.h" + + +/* r8, or pair r8, r9, or aggregate up to r8-r11. */ +static const Dwarf_Op loc_intreg[] = + { + { .atom = DW_OP_reg8 }, { .atom = DW_OP_piece, .number = 8 }, + { .atom = DW_OP_reg9 }, { .atom = DW_OP_piece, .number = 8 }, + { .atom = DW_OP_reg10 }, { .atom = DW_OP_piece, .number = 8 }, + { .atom = DW_OP_reg11 }, { .atom = DW_OP_piece, .number = 8 }, + }; +#define nloc_intreg 1 +#define nloc_intregs(n) (2 * (n)) + +/* f8, or aggregate up to f8-f15. */ +#define DEFINE_FPREG(size) \ + static const Dwarf_Op loc_fpreg_##size[] = \ + { \ + { .atom = DW_OP_regx, .number = 128 + 8 }, \ + { .atom = DW_OP_piece, .number = size }, \ + { .atom = DW_OP_regx, .number = 128 + 9 }, \ + { .atom = DW_OP_piece, .number = size }, \ + { .atom = DW_OP_regx, .number = 128 + 10 }, \ + { .atom = DW_OP_piece, .number = size }, \ + { .atom = DW_OP_regx, .number = 128 + 11 }, \ + { .atom = DW_OP_piece, .number = size }, \ + { .atom = DW_OP_regx, .number = 128 + 12 }, \ + { .atom = DW_OP_piece, .number = size }, \ + { .atom = DW_OP_regx, .number = 128 + 13 }, \ + { .atom = DW_OP_piece, .number = size }, \ + { .atom = DW_OP_regx, .number = 128 + 14 }, \ + { .atom = DW_OP_piece, .number = size }, \ + { .atom = DW_OP_regx, .number = 128 + 15 }, \ + { .atom = DW_OP_piece, .number = size }, \ + } +#define nloc_fpreg 1 +#define nloc_fpregs(n) (2 * (n)) + +DEFINE_FPREG (4); +DEFINE_FPREG (8); +DEFINE_FPREG (10); + +#undef DEFINE_FPREG + + +/* The return value is a structure and is actually stored in stack space + passed in a hidden argument by the caller. But, the compiler + helpfully returns the address of that space in r8. */ +static const Dwarf_Op loc_aggregate[] = + { + { .atom = DW_OP_breg8, .number = 0 } + }; +#define nloc_aggregate 1 + + +int +ia64_return_value_location (Dwarf_Die *functypedie, const Dwarf_Op **locp) +{ + /* Start with the function's type, and get the DW_AT_type attribute, + which is the type of the return value. */ + + Dwarf_Attribute attr_mem; + Dwarf_Attribute *attr = dwarf_attr (functypedie, DW_AT_type, &attr_mem); + if (attr == NULL) + /* The function has no return value, like a `void' function in C. */ + return 0; + + Dwarf_Die die_mem; + Dwarf_Die *typedie = dwarf_formref_die (attr, &die_mem); + int tag = dwarf_tag (typedie); + + /* Follow typedefs and qualifiers to get to the actual type. */ + while (tag == DW_TAG_typedef + || tag == DW_TAG_const_type || tag == DW_TAG_volatile_type + || tag == DW_TAG_restrict_type || tag == DW_TAG_mutable_type) + { + attr = dwarf_attr (typedie, DW_AT_type, &attr_mem); + typedie = dwarf_formref_die (attr, &die_mem); + tag = dwarf_tag (typedie); + } + + Dwarf_Word size; + switch (tag) + { + case -1: + return -1; + + case DW_TAG_subrange_type: + if (! dwarf_hasattr (typedie, DW_AT_byte_size)) + { + attr = dwarf_attr (typedie, DW_AT_type, &attr_mem); + typedie = dwarf_formref_die (attr, &die_mem); + tag = dwarf_tag (typedie); + } + /* Fall through. */ + + case DW_TAG_base_type: + case DW_TAG_enumeration_type: + case DW_TAG_pointer_type: + case DW_TAG_ptr_to_member_type: + if (dwarf_formudata (dwarf_attr (typedie, DW_AT_byte_size, + &attr_mem), &size) != 0) + { + if (tag == DW_TAG_pointer_type || tag == DW_TAG_ptr_to_member_type) + size = 8; + else + return -1; + } + if (tag == DW_TAG_base_type) + { + Dwarf_Word encoding; + if (dwarf_formudata (dwarf_attr (typedie, DW_AT_encoding, + &attr_mem), &encoding) != 0) + return -1; + + switch (encoding) + { + case DW_ATE_float: + switch (size) + { + case 4: /* float */ + *locp = loc_fpreg_4; + return nloc_fpreg; + case 8: /* double */ + *locp = loc_fpreg_8; + return nloc_fpreg; + case 10: /* x86-style long double, not really used */ + *locp = loc_fpreg_10; + return nloc_fpreg; + case 16: /* long double, IEEE quad format */ + *locp = loc_intreg; + return nloc_intregs (2); + } + return -2; + + case DW_ATE_complex_float: + switch (size) + { + case 4 * 2: /* complex float */ + *locp = loc_fpreg_4; + return nloc_fpregs (2); + case 8 * 2: /* complex double */ + *locp = loc_fpreg_8; + return nloc_fpregs (2); + case 10 * 2: /* complex long double (x86-style) */ + *locp = loc_fpreg_10; + return nloc_fpregs (2); + case 16 * 2: /* complex long double (IEEE quad) */ + *locp = loc_intreg; + return nloc_intregs (4); + } + return -2; + } + } + + intreg: + *locp = loc_intreg; + if (size <= 8) + return nloc_intreg; + if (size <= 32) + return nloc_intregs ((size + 7) / 8); + + large: + *locp = loc_aggregate; + return nloc_aggregate; + + case DW_TAG_structure_type: + case DW_TAG_class_type: + case DW_TAG_union_type: + case DW_TAG_array_type: + if (dwarf_formudata (dwarf_attr (typedie, DW_AT_byte_size, + &attr_mem), &size) != 0) + return -1; + if (size > 32) + goto large; + + /* XXX + Must examine the fields in picayune ways to determine the + actual answer. If it qualifies as an HFA (all floats) + then it should be returned in fp regs. + */ + + goto intreg; + } + + /* XXX We don't have a good way to return specific errors from ebl calls. + This value means we do not understand the type, but it is well-formed + DWARF and might be valid. */ + return -2; +} |