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-rw-r--r--bfd/bfd-in2.h3
-rw-r--r--bfd/elf32-arm.c208
-rw-r--r--bfd/libbfd.h1
-rw-r--r--bfd/reloc.c5
4 files changed, 205 insertions, 12 deletions
diff --git a/bfd/bfd-in2.h b/bfd/bfd-in2.h
index 858bb29..c1b5341 100644
--- a/bfd/bfd-in2.h
+++ b/bfd/bfd-in2.h
@@ -3089,6 +3089,9 @@ pc-relative or some form of GOT-indirect relocation. */
BFD_RELOC_ARM_LDC_SB_G1,
BFD_RELOC_ARM_LDC_SB_G2,
+/* Annotation of BX instructions. */
+ BFD_RELOC_ARM_V4BX,
+
/* These relocs are only used within the ARM assembler. They are not
(at present) written to any object files. */
BFD_RELOC_ARM_IMMEDIATE,
diff --git a/bfd/elf32-arm.c b/bfd/elf32-arm.c
index ec88703..7218ba8 100644
--- a/bfd/elf32-arm.c
+++ b/bfd/elf32-arm.c
@@ -1773,7 +1773,8 @@ static const struct elf32_arm_reloc_map elf32_arm_reloc_map[] =
{BFD_RELOC_ARM_LDRS_SB_G2, R_ARM_LDRS_SB_G2},
{BFD_RELOC_ARM_LDC_SB_G0, R_ARM_LDC_SB_G0},
{BFD_RELOC_ARM_LDC_SB_G1, R_ARM_LDC_SB_G1},
- {BFD_RELOC_ARM_LDC_SB_G2, R_ARM_LDC_SB_G2}
+ {BFD_RELOC_ARM_LDC_SB_G2, R_ARM_LDC_SB_G2},
+ {BFD_RELOC_ARM_V4BX, R_ARM_V4BX}
};
static reloc_howto_type *
@@ -1904,6 +1905,9 @@ typedef unsigned short int insn16;
#define VFP11_ERRATUM_VENEER_SECTION_NAME ".vfp11_veneer"
#define VFP11_ERRATUM_VENEER_ENTRY_NAME "__vfp11_veneer_%x"
+#define ARM_BX_GLUE_SECTION_NAME ".v4_bx"
+#define ARM_BX_GLUE_ENTRY_NAME "__bx_r%d"
+
/* The name of the dynamic interpreter. This is put in the .interp
section. */
#define ELF_DYNAMIC_INTERPRETER "/usr/lib/ld.so.1"
@@ -2171,6 +2175,13 @@ struct elf32_arm_link_hash_table
/* The size in bytes of the section containing the ARM-to-Thumb glue. */
bfd_size_type arm_glue_size;
+ /* The size in bytes of section containing the ARMv4 BX veneers. */
+ bfd_size_type bx_glue_size;
+
+ /* Offsets of ARMv4 BX veneers. Bit1 set if present, and Bit0 set when
+ veneer has been populated. */
+ bfd_vma bx_glue_offset[15];
+
/* The size in bytes of the section containing glue for VFP11 erratum
veneers. */
bfd_size_type vfp11_erratum_glue_size;
@@ -2188,7 +2199,9 @@ struct elf32_arm_link_hash_table
/* The relocation to use for R_ARM_TARGET2 relocations. */
int target2_reloc;
- /* Nonzero to fix BX instructions for ARMv4 targets. */
+ /* 0 = Ignore R_ARM_V4BX.
+ 1 = Convert BX to MOV PC.
+ 2 = Generate v4 interworing stubs. */
int fix_v4bx;
/* Nonzero if the ARM/Thumb BLX instructions are available for use. */
@@ -2469,6 +2482,8 @@ elf32_arm_link_hash_table_create (bfd *abfd)
ret->srelplt2 = NULL;
ret->thumb_glue_size = 0;
ret->arm_glue_size = 0;
+ ret->bx_glue_size = 0;
+ memset (ret->bx_glue_offset, 0, sizeof(ret->bx_glue_offset));
ret->vfp11_fix = BFD_ARM_VFP11_FIX_NONE;
ret->vfp11_erratum_glue_size = 0;
ret->num_vfp11_fixes = 0;
@@ -2626,6 +2641,11 @@ static const insn32 t2a3_b_insn = 0xea000000;
#define VFP11_ERRATUM_VENEER_SIZE 8
+#define ARM_BX_VENEER_SIZE 12
+static const insn32 armbx1_tst_insn = 0xe3100001;
+static const insn32 armbx2_moveq_insn = 0x01a0f000;
+static const insn32 armbx3_bx_insn = 0xe12fff10;
+
#ifndef ELFARM_NABI_C_INCLUDED
bfd_boolean
bfd_elf32_arm_allocate_interworking_sections (struct bfd_link_info * info)
@@ -2684,6 +2704,21 @@ bfd_elf32_arm_allocate_interworking_sections (struct bfd_link_info * info)
s->contents = foo;
}
+ if (globals->bx_glue_size != 0)
+ {
+ BFD_ASSERT (globals->bfd_of_glue_owner != NULL);
+
+ s = bfd_get_section_by_name (globals->bfd_of_glue_owner,
+ ARM_BX_GLUE_SECTION_NAME);
+
+ BFD_ASSERT (s != NULL);
+
+ foo = bfd_alloc (globals->bfd_of_glue_owner, globals->bx_glue_size);
+
+ BFD_ASSERT (s->size == globals->bx_glue_size);
+ s->contents = foo;
+ }
+
return TRUE;
}
@@ -2835,6 +2870,64 @@ record_thumb_to_arm_glue (struct bfd_link_info *link_info,
}
+/* Allocate space for ARMv4 BX veneers. */
+
+static void
+record_arm_bx_glue (struct bfd_link_info * link_info, int reg)
+{
+ asection * s;
+ struct elf32_arm_link_hash_table *globals;
+ char *tmp_name;
+ struct elf_link_hash_entry *myh;
+ struct bfd_link_hash_entry *bh;
+ bfd_vma val;
+
+ /* BX PC does not need a veneer. */
+ if (reg == 15)
+ return;
+
+ globals = elf32_arm_hash_table (link_info);
+
+ BFD_ASSERT (globals != NULL);
+ BFD_ASSERT (globals->bfd_of_glue_owner != NULL);
+
+ /* Check if this veneer has already been allocated. */
+ if (globals->bx_glue_offset[reg])
+ return;
+
+ s = bfd_get_section_by_name
+ (globals->bfd_of_glue_owner, ARM_BX_GLUE_SECTION_NAME);
+
+ BFD_ASSERT (s != NULL);
+
+ /* Add symbol for veneer. */
+ tmp_name = bfd_malloc ((bfd_size_type) strlen (ARM_BX_GLUE_ENTRY_NAME) + 1);
+
+ BFD_ASSERT (tmp_name);
+
+ sprintf (tmp_name, ARM_BX_GLUE_ENTRY_NAME, reg);
+
+ myh = elf_link_hash_lookup
+ (&(globals)->root, tmp_name, FALSE, FALSE, FALSE);
+
+ BFD_ASSERT (myh == NULL);
+
+ bh = NULL;
+ val = globals->bx_glue_size;
+ _bfd_generic_link_add_one_symbol (link_info, globals->bfd_of_glue_owner,
+ tmp_name, BSF_FUNCTION | BSF_LOCAL, s, val,
+ NULL, TRUE, FALSE, &bh);
+
+ myh = (struct elf_link_hash_entry *) bh;
+ myh->type = ELF_ST_INFO (STB_LOCAL, STT_FUNC);
+ myh->forced_local = 1;
+
+ s->size += ARM_BX_VENEER_SIZE;
+ globals->bx_glue_offset[reg] = globals->bx_glue_size | 2;
+ globals->bx_glue_size += ARM_BX_VENEER_SIZE;
+}
+
+
/* Add an entry to the code/data map for section SEC. */
static void
@@ -3058,6 +3151,24 @@ bfd_elf32_arm_add_glue_sections_to_bfd (bfd *abfd,
sec->gc_mark = 1;
}
+ sec = bfd_get_section_by_name (abfd, ARM_BX_GLUE_SECTION_NAME);
+
+ if (sec == NULL)
+ {
+ flags = (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS | SEC_IN_MEMORY
+ | SEC_CODE | SEC_READONLY);
+
+ sec = bfd_make_section_with_flags (abfd,
+ ARM_BX_GLUE_SECTION_NAME,
+ flags);
+
+ if (sec == NULL
+ || !bfd_set_section_alignment (abfd, sec, 2))
+ return FALSE;
+
+ sec->gc_mark = 1;
+ }
+
return TRUE;
}
@@ -3177,7 +3288,8 @@ bfd_elf32_arm_process_before_allocation (bfd *abfd,
&& r_type != R_ARM_CALL
&& r_type != R_ARM_JUMP24
&& r_type != R_ARM_THM_CALL
- && r_type != R_ARM_THM_JUMP24)
+ && r_type != R_ARM_THM_JUMP24
+ && (r_type != R_ARM_V4BX || globals->fix_v4bx < 2))
continue;
/* Get the section contents if we haven't done so already. */
@@ -3194,6 +3306,15 @@ bfd_elf32_arm_process_before_allocation (bfd *abfd,
}
}
+ if (r_type == R_ARM_V4BX)
+ {
+ int reg;
+
+ reg = bfd_get_32 (abfd, contents + irel->r_offset) & 0xf;
+ record_arm_bx_glue (link_info, reg);
+ continue;
+ }
+
/* If the relocation is not against a symbol it cannot concern us. */
h = NULL;
@@ -4332,6 +4453,43 @@ elf32_arm_to_thumb_export_stub (struct elf_link_hash_entry *h, void * inf)
return TRUE;
}
+/* Populate ARMv4 BX veneers. Returns the absolute adress of the veneer. */
+
+static bfd_vma
+elf32_arm_bx_glue (struct bfd_link_info * info, int reg)
+{
+ bfd_byte *p;
+ bfd_vma glue_addr;
+ asection *s;
+ struct elf32_arm_link_hash_table *globals;
+
+ globals = elf32_arm_hash_table (info);
+
+ BFD_ASSERT (globals != NULL);
+ BFD_ASSERT (globals->bfd_of_glue_owner != NULL);
+
+ s = bfd_get_section_by_name (globals->bfd_of_glue_owner,
+ ARM_BX_GLUE_SECTION_NAME);
+ BFD_ASSERT (s != NULL);
+ BFD_ASSERT (s->contents != NULL);
+ BFD_ASSERT (s->output_section != NULL);
+
+ BFD_ASSERT (globals->bx_glue_offset[reg] & 2);
+
+ glue_addr = globals->bx_glue_offset[reg] & ~(bfd_vma)3;
+
+ if ((globals->bx_glue_offset[reg] & 1) == 0)
+ {
+ p = s->contents + glue_addr;
+ bfd_put_32 (globals->obfd, armbx1_tst_insn + (reg << 16), p);
+ bfd_put_32 (globals->obfd, armbx2_moveq_insn + reg, p + 4);
+ bfd_put_32 (globals->obfd, armbx3_bx_insn + reg, p + 8);
+ globals->bx_glue_offset[reg] |= 1;
+ }
+
+ return glue_addr + s->output_section->vma + s->output_offset;
+}
+
/* Generate Arm stubs for exported Thumb symbols. */
static void
elf32_arm_begin_write_processing (bfd *abfd ATTRIBUTE_UNUSED,
@@ -5710,18 +5868,32 @@ elf32_arm_final_link_relocate (reloc_howto_type * howto,
case R_ARM_V4BX:
if (globals->fix_v4bx)
- {
- bfd_vma insn = bfd_get_32 (input_bfd, hit_data);
+ {
+ bfd_vma insn = bfd_get_32 (input_bfd, hit_data);
- /* Ensure that we have a BX instruction. */
- BFD_ASSERT ((insn & 0x0ffffff0) == 0x012fff10);
+ /* Ensure that we have a BX instruction. */
+ BFD_ASSERT ((insn & 0x0ffffff0) == 0x012fff10);
- /* Preserve Rm (lowest four bits) and the condition code
- (highest four bits). Other bits encode MOV PC,Rm. */
- insn = (insn & 0xf000000f) | 0x01a0f000;
+ if (globals->fix_v4bx == 2 && (insn & 0xf) != 0xf)
+ {
+ /* Branch to veneer. */
+ bfd_vma glue_addr;
+ glue_addr = elf32_arm_bx_glue (info, insn & 0xf);
+ glue_addr -= input_section->output_section->vma
+ + input_section->output_offset
+ + rel->r_offset + 8;
+ insn = (insn & 0xf0000000) | 0x0a000000
+ | ((glue_addr >> 2) & 0x00ffffff);
+ }
+ else
+ {
+ /* Preserve Rm (lowest four bits) and the condition code
+ (highest four bits). Other bits encode MOV PC,Rm. */
+ insn = (insn & 0xf000000f) | 0x01a0f000;
+ }
- bfd_put_32 (input_bfd, insn, hit_data);
- }
+ bfd_put_32 (input_bfd, insn, hit_data);
+ }
return bfd_reloc_ok;
case R_ARM_MOVW_ABS_NC:
@@ -9732,6 +9904,18 @@ elf32_arm_output_arch_local_syms (bfd *output_bfd,
}
}
+ /* ARMv4 BX veneers. */
+ if (htab->bx_glue_size > 0)
+ {
+ osi.sec = bfd_get_section_by_name (htab->bfd_of_glue_owner,
+ ARM_BX_GLUE_SECTION_NAME);
+
+ osi.sec_shndx = _bfd_elf_section_from_bfd_section
+ (output_bfd, osi.sec->output_section);
+
+ elf32_arm_ouput_plt_map_sym (&osi, ARM_MAP_ARM, 0);
+ }
+
/* Finally, output mapping symbols for the PLT. */
if (!htab->splt || htab->splt->size == 0)
return TRUE;
diff --git a/bfd/libbfd.h b/bfd/libbfd.h
index 4d83a4c..cb6544a 100644
--- a/bfd/libbfd.h
+++ b/bfd/libbfd.h
@@ -1282,6 +1282,7 @@ static const char *const bfd_reloc_code_real_names[] = { "@@uninitialized@@",
"BFD_RELOC_ARM_LDC_SB_G0",
"BFD_RELOC_ARM_LDC_SB_G1",
"BFD_RELOC_ARM_LDC_SB_G2",
+ "BFD_RELOC_ARM_V4BX",
"BFD_RELOC_ARM_IMMEDIATE",
"BFD_RELOC_ARM_ADRL_IMMEDIATE",
"BFD_RELOC_ARM_T32_IMMEDIATE",
diff --git a/bfd/reloc.c b/bfd/reloc.c
index f413ced..027ede0 100644
--- a/bfd/reloc.c
+++ b/bfd/reloc.c
@@ -2925,6 +2925,11 @@ ENUMDOC
ARM group relocations.
ENUM
+ BFD_RELOC_ARM_V4BX
+ENUMDOC
+ Annotation of BX instructions.
+
+ENUM
BFD_RELOC_ARM_IMMEDIATE
ENUMX
BFD_RELOC_ARM_ADRL_IMMEDIATE