progmem_section is a section to put jump tables in.
This patch puts jump tables in individual sections if
-ffunction-section is on and does some more cleanup around
that, i.e. implement TARGET_ASM_FUNCTION_RODATA_SECTION hook.
progmem_section is renamed to progmem_swtable_section and is
local to avr.c now.
What I don't understand is the old restriction that ASM_OUTPUT_ALIGN
only printed .p2align for powers > 1; I changed that to >= 1 so that
jump tables get aligned properly.
Passed without regressions.
Ok to commit?
Johann
* config/avr/avr.h (progmem_section): Remove Declaration.
(ASM_OUTPUT_ALIGN): Output .p2align for powers >= 1.
* config/avr/avr.c (progmem_section): Make static and rename to
progmem_swtable_section.
(avr_output_addr_vec_elt): No need to switch sections.
(avr_asm_init_sections): Use output_section_asm_op as section
callback for progmem_swtable_section.
(avr_output_progmem_section_asm_op): Remove Function.
(TARGET_ASM_FUNCTION_RODATA_SECTION): New Define.
(avr_asm_function_rodata_section): New static Function.
* config/avr/elf.h (ASM_OUTPUT_BEFORE_CASE_LABEL): Define to
output alignment 2**1 for jump tables.
Index: config/avr/elf.h
===================================================================
--- config/avr/elf.h (revision 178062)
+++ config/avr/elf.h (working copy)
@@ -37,9 +37,10 @@
#define ASM_DECLARE_FUNCTION_NAME(FILE, NAME, DECL) \
avr_asm_declare_function_name ((FILE), (NAME), (DECL))
+/* Output alignment 2**1 for jump tables. */
#undef ASM_OUTPUT_BEFORE_CASE_LABEL
#define ASM_OUTPUT_BEFORE_CASE_LABEL(FILE, PREFIX, NUM, TABLE) \
- switch_to_section (progmem_section);
+ ASM_OUTPUT_ALIGN ((FILE), 1);
/* Be conservative in crtstuff.c. */
#undef INIT_SECTION_ASM_OP
Index: config/avr/avr.c
===================================================================
--- config/avr/avr.c (revision 178067)
+++ config/avr/avr.c (working copy)
@@ -113,6 +113,7 @@ static void avr_function_arg_advance (cu
static bool avr_function_ok_for_sibcall (tree, tree);
static void avr_asm_named_section (const char *name, unsigned int flags, tree decl);
static void avr_encode_section_info (tree, rtx, int);
+static section* avr_asm_function_rodata_section (tree);
/* Allocate registers from r25 to r8 for parameters for function calls. */
#define FIRST_CUM_REG 26
@@ -135,7 +136,8 @@ const struct base_arch_s *avr_current_ar
/* Current device. */
const struct mcu_type_s *avr_current_device;
-section *progmem_section;
+/* Section to put switch tables in. */
+static GTY(()) section *progmem_swtable_section;
/* To track if code will use .bss and/or .data. */
bool avr_need_clear_bss_p = false;
@@ -263,6 +265,8 @@ static const struct attribute_spec avr_a
#undef TARGET_EXPAND_BUILTIN
#define TARGET_EXPAND_BUILTIN avr_expand_builtin
+#undef TARGET_ASM_FUNCTION_RODATA_SECTION
+#define TARGET_ASM_FUNCTION_RODATA_SECTION avr_asm_function_rodata_section
struct gcc_target targetm = TARGET_INITIALIZER;
@@ -5036,18 +5040,6 @@ avr_insert_attributes (tree node, tree *
}
}
-/* A get_unnamed_section callback for switching to progmem_section. */
-
-static void
-avr_output_progmem_section_asm_op (const void *arg ATTRIBUTE_UNUSED)
-{
- fprintf (asm_out_file,
- "\t.section .progmem.gcc_sw_table, \"%s\", @progbits\n",
- AVR_HAVE_JMP_CALL ? "a" : "ax");
- /* Should already be aligned, this is just to be safe if it isn't. */
- fprintf (asm_out_file, "\t.p2align 1\n");
-}
-
/* Implement `ASM_OUTPUT_ALIGNED_DECL_LOCAL'. */
/* Implement `ASM_OUTPUT_ALIGNED_DECL_COMMON'. */
@@ -5098,9 +5090,23 @@ avr_output_bss_section_asm_op (const voi
static void
avr_asm_init_sections (void)
{
- progmem_section = get_unnamed_section (AVR_HAVE_JMP_CALL ? 0 : SECTION_CODE,
- avr_output_progmem_section_asm_op,
- NULL);
+ /* Set up a section for jump tables. Alignment is handled by
+ ASM_OUTPUT_BEFORE_CASE_LABEL. */
+
+ if (AVR_HAVE_JMP_CALL)
+ {
+ progmem_swtable_section
+ = get_unnamed_section (0, output_section_asm_op,
+ "\t.section\t.progmem.gcc_sw_table"
+ ",\"a\",@progbits");
+ }
+ else
+ {
+ progmem_swtable_section
+ = get_unnamed_section (SECTION_CODE, output_section_asm_op,
+ "\t.section\t.progmem.gcc_sw_table"
+ ",\"ax\",@progbits");
+ }
/* Override section callbacks to keep track of `avr_need_clear_bss_p'
resp. `avr_need_copy_data_p'. */
@@ -5111,6 +5117,36 @@ avr_asm_init_sections (void)
}
+/* Implement `TARGET_ASM_FUNCTION_RODATA_SECTION'. */
+
+static section*
+avr_asm_function_rodata_section (tree decl)
+{
+ /* If a function is unused and optimized out by -ffunction-sections and
+ --gc-sections, ensure that the same will happen for its jump tables
+ by putting them into individual sections. */
+
+ if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
+ {
+ const char *name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
+
+ if (flag_function_sections
+ && STR_PREFIX_P (name, ".text."))
+ {
+ size_t len = strlen (name) + 1;
+ char *rname = (char *) alloca (len + 16);
+
+ strcat (stpcpy (rname, ".progmem.gcc_sw_table"), name + 5);
+
+ return get_section (rname,
+ AVR_HAVE_JMP_CALL ? 0 : SECTION_CODE, decl);
+ }
+ }
+
+ return progmem_swtable_section;
+}
+
+
/* Implement `TARGET_ASM_NAMED_SECTION'. */
/* Track need of __do_clear_bss, __do_copy_data for named sections. */
@@ -6693,7 +6729,6 @@ avr_output_bld (rtx operands[], int bit_
void
avr_output_addr_vec_elt (FILE *stream, int value)
{
- switch_to_section (progmem_section);
if (AVR_HAVE_JMP_CALL)
fprintf (stream, "\t.word gs(.L%d)\n", value);
else
Index: config/avr/avr.h
===================================================================
--- config/avr/avr.h (revision 178064)
+++ config/avr/avr.h (working copy)
@@ -127,10 +127,6 @@ extern const struct base_arch_s avr_arch
#define TARGET_CPU_CPP_BUILTINS() avr_cpu_cpp_builtins (pfile)
-#if !defined(IN_LIBGCC2) && !defined(IN_TARGET_LIBS)
-extern GTY(()) section *progmem_section;
-#endif
-
#define AVR_HAVE_JMP_CALL (avr_current_arch->have_jmp_call && !TARGET_SHORT_CALLS)
#define AVR_HAVE_MUL (avr_current_arch->have_mul)
#define AVR_HAVE_MOVW (avr_current_arch->have_movw_lpmx)
@@ -523,8 +519,8 @@ do { \
#define ASM_OUTPUT_ALIGN(STREAM, POWER) \
do { \
- if ((POWER) > 1) \
- fprintf (STREAM, "\t.p2align\t%d\n", POWER); \
+ if ((POWER) >= 1) \
+ fprintf (STREAM, "\t.p2align\t%d\n", POWER); \
} while (0)
#define CASE_VECTOR_MODE HImode
