Squashed 'third_party/elfutils/' content from commit 555e15e
Change-Id: I61cde98949e47e5c8c09c33260de17f30921be79
git-subtree-dir: third_party/elfutils
git-subtree-split: 555e15ebe8bf1eb33d00747173cfc80cc65648a4
diff --git a/backends/ia64_retval.c b/backends/ia64_retval.c
new file mode 100644
index 0000000..03ea4d8
--- /dev/null
+++ b/backends/ia64_retval.c
@@ -0,0 +1,366 @@
+/* Function return value location for IA64 ABI.
+ Copyright (C) 2006-2010, 2014 Red Hat, Inc.
+ This file is part of elfutils.
+
+ This file is free software; you can redistribute it and/or modify
+ it under the terms of either
+
+ * the GNU Lesser General Public License as published by the Free
+ Software Foundation; either version 3 of the License, or (at
+ your option) any later version
+
+ or
+
+ * 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
+
+ or both in parallel, as here.
+
+ 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 copies of the GNU General Public License and
+ the GNU Lesser General Public License along with this program. If
+ not, see <http://www.gnu.org/licenses/>. */
+
+#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
+
+
+static inline int
+compute_hfa (const Dwarf_Op *loc, int nregs,
+ const Dwarf_Op **locp, int fpregs_used)
+{
+ if (fpregs_used == 0)
+ *locp = loc;
+ else if (*locp != loc)
+ return 9;
+ return fpregs_used + nregs;
+}
+
+/* If this type is an HFA small enough to be returned in FP registers,
+ return the number of registers to use. Otherwise 9, or -1 for errors. */
+static int
+hfa_type (Dwarf_Die *typedie, Dwarf_Word size,
+ const Dwarf_Op **locp, int fpregs_used)
+{
+ /* Descend the type structure, counting elements and finding their types.
+ If we find a datum that's not an FP type (and not quad FP), punt.
+ If we find a datum that's not the same FP type as the first datum, punt.
+ If we count more than eight total homogeneous FP data, punt. */
+
+ int tag = DWARF_TAG_OR_RETURN (typedie);
+ switch (tag)
+ {
+ Dwarf_Attribute attr_mem;
+
+ case -1:
+ return -1;
+
+ case DW_TAG_base_type:;
+ Dwarf_Word encoding;
+ if (dwarf_formudata (dwarf_attr_integrate (typedie, DW_AT_encoding,
+ &attr_mem), &encoding) != 0)
+ return -1;
+
+#define hfa(loc, nregs) compute_hfa(loc, nregs, locp, fpregs_used)
+ switch (encoding)
+ {
+ case DW_ATE_float:
+ switch (size)
+ {
+ case 4: /* float */
+ return hfa (loc_fpreg_4, 1);
+ case 8: /* double */
+ return hfa (loc_fpreg_8, 1);
+ case 10: /* x86-style long double, not really used */
+ return hfa (loc_fpreg_10, 1);
+ }
+ break;
+
+ case DW_ATE_complex_float:
+ switch (size)
+ {
+ case 4 * 2: /* complex float */
+ return hfa (loc_fpreg_4, 2);
+ case 8 * 2: /* complex double */
+ return hfa (loc_fpreg_8, 2);
+ case 10 * 2: /* complex long double (x86-style) */
+ return hfa (loc_fpreg_10, 2);
+ }
+ break;
+ }
+ break;
+
+ case DW_TAG_structure_type:
+ case DW_TAG_class_type:
+ case DW_TAG_union_type:;
+ Dwarf_Die child_mem;
+ switch (dwarf_child (typedie, &child_mem))
+ {
+ default:
+ return -1;
+
+ case 1: /* No children: empty struct. */
+ break;
+
+ case 0:; /* Look at each element. */
+ int max_used = fpregs_used;
+ do
+ switch (dwarf_tag (&child_mem))
+ {
+ case -1:
+ return -1;
+
+ case DW_TAG_member:;
+ Dwarf_Die child_type_mem;
+ Dwarf_Die *child_typedie
+ = dwarf_formref_die (dwarf_attr_integrate (&child_mem,
+ DW_AT_type,
+ &attr_mem),
+ &child_type_mem);
+ Dwarf_Word child_size;
+ if (dwarf_aggregate_size (child_typedie, &child_size) != 0)
+ return -1;
+ if (tag == DW_TAG_union_type)
+ {
+ int used = hfa_type (child_typedie, child_size,
+ locp, fpregs_used);
+ if (used < 0 || used > 8)
+ return used;
+ if (used > max_used)
+ max_used = used;
+ }
+ else
+ {
+ fpregs_used = hfa_type (child_typedie, child_size,
+ locp, fpregs_used);
+ if (fpregs_used < 0 || fpregs_used > 8)
+ return fpregs_used;
+ }
+ }
+ while (dwarf_siblingof (&child_mem, &child_mem) == 0);
+ if (tag == DW_TAG_union_type)
+ fpregs_used = max_used;
+ break;
+ }
+ break;
+
+ case DW_TAG_array_type:
+ if (size == 0)
+ break;
+
+ Dwarf_Die base_type_mem;
+ Dwarf_Die *base_typedie
+ = dwarf_formref_die (dwarf_attr_integrate (typedie, DW_AT_type,
+ &attr_mem),
+ &base_type_mem);
+ Dwarf_Word base_size;
+ if (dwarf_aggregate_size (base_typedie, &base_size) != 0)
+ return -1;
+
+ int used = hfa_type (base_typedie, base_size, locp, 0);
+ if (used < 0 || used > 8)
+ return used;
+ if (size % (*locp)[1].number != 0)
+ return 0;
+ fpregs_used += used * (size / (*locp)[1].number);
+ break;
+
+ default:
+ return 9;
+ }
+
+ return fpregs_used;
+}
+
+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_Die die_mem, *typedie = &die_mem;
+ int tag = dwarf_peeled_die_type (functypedie, typedie);
+ if (tag <= 0)
+ return tag;
+
+ Dwarf_Word size;
+ switch (tag)
+ {
+ case -1:
+ return -1;
+
+ case DW_TAG_subrange_type:
+ if (! dwarf_hasattr_integrate (typedie, DW_AT_byte_size))
+ {
+ Dwarf_Attribute attr_mem, *attr;
+ attr = dwarf_attr_integrate (typedie, DW_AT_type, &attr_mem);
+ typedie = dwarf_formref_die (attr, &die_mem);
+ tag = DWARF_TAG_OR_RETURN (typedie);
+ }
+ FALLTHROUGH;
+
+ case DW_TAG_base_type:
+ case DW_TAG_enumeration_type:
+ case DW_TAG_pointer_type:
+ case DW_TAG_ptr_to_member_type:
+ {
+ Dwarf_Attribute attr_mem;
+ if (dwarf_formudata (dwarf_attr_integrate (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_Attribute attr_mem;
+ Dwarf_Word encoding;
+ if (dwarf_formudata (dwarf_attr_integrate (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_aggregate_size (typedie, &size) != 0)
+ return -1;
+
+ /* If this qualifies as an homogeneous floating-point aggregate
+ (HFA), then it should be returned in FP regs. */
+ int nfpreg = hfa_type (typedie, size, locp, 0);
+ if (nfpreg < 0)
+ return nfpreg;
+ else if (nfpreg > 0 && nfpreg <= 8)
+ return nfpreg == 1 ? nloc_fpreg : nloc_fpregs (nfpreg);
+
+ if (size > 32)
+ goto large;
+
+ 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;
+}