diff options
| author | Roland McGrath <[email protected]> | 2005-11-17 03:16:00 +0000 |
|---|---|---|
| committer | Roland McGrath <[email protected]> | 2005-11-17 03:16:00 +0000 |
| commit | e47ab76f02c2a4f4d802ec298969ba67956435fe (patch) | |
| tree | 39dccb25273f15a488632c952738909f860c4b71 /backends/alpha_retval.c | |
| parent | d7f8d0caa7a357f9f4765e5dc93255f5057eba2e (diff) | |
Update new test after merge.
Diffstat (limited to 'backends/alpha_retval.c')
| -rw-r--r-- | backends/alpha_retval.c | 148 |
1 files changed, 148 insertions, 0 deletions
diff --git a/backends/alpha_retval.c b/backends/alpha_retval.c new file mode 100644 index 00000000..e1301515 --- /dev/null +++ b/backends/alpha_retval.c @@ -0,0 +1,148 @@ +/* Function return value location for Alpha ELF ABI. + Copyright (C) 2005 Red Hat, Inc. + + This program is Open Source software; you can redistribute it and/or + modify it under the terms of the Open Software License version 1.0 as + published by the Open Source Initiative. + + You should have received a copy of the Open Software License along + with this program; if not, you may obtain a copy of the Open Software + License version 1.0 from http://www.opensource.org/licenses/osl.php or + by writing the Open Source Initiative c/o Lawrence Rosen, Esq., + 3001 King Ranch Road, Ukiah, CA 95482. */ + +#ifdef HAVE_CONFIG_H +# include <config.h> +#endif + +#include <assert.h> +#include <dwarf.h> + +#define BACKEND alpha_ +#include "libebl_CPU.h" + + +/* $0. */ +static const Dwarf_Op loc_intreg[] = + { + { .atom = DW_OP_reg0 } + }; +#define nloc_intreg 1 + +/* $f0, or pair $f0, $f1. */ +static const Dwarf_Op loc_fpreg[] = + { + { .atom = DW_OP_regx, .number = 32 }, { .atom = DW_OP_piece, .number = 4 }, + { .atom = DW_OP_regx, .number = 33 }, { .atom = DW_OP_piece, .number = 4 }, + }; +#define nloc_fpreg 1 +#define nloc_fpregpair 4 + +/* 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 $0. */ +static const Dwarf_Op loc_aggregate[] = + { + { .atom = DW_OP_breg0, .number = 0 } + }; +#define nloc_aggregate 1 + +int +alpha_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); + } + + 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: + { + Dwarf_Word size; + 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; + + *locp = loc_fpreg; + if (encoding == DW_ATE_float) + { + if (size <= 8) + return nloc_fpreg; + goto aggregate; + } + if (encoding == DW_ATE_complex_float) + { + if (size <= 8 * 2) + return nloc_fpregpair; + goto aggregate; + } + } + if (size <= 8) + { + *locp = loc_intreg; + return nloc_intreg; + } + } + + /* Else fall through. */ + + case DW_TAG_structure_type: + case DW_TAG_class_type: + case DW_TAG_union_type: + case DW_TAG_string_type: + case DW_TAG_array_type: + aggregate: + *locp = loc_aggregate; + return nloc_aggregate; + } + + /* 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; +} |
