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authorKyrylo Tkachov <kyrylo.tkachov@arm.com>2015-08-04 10:06:51 +0000
committerKyrylo Tkachov <ktkachov@gcc.gnu.org>2015-08-04 10:06:51 +0000
commit361fb3ee79f07fcff6c34acd1ccde520f4935c7e (patch)
tree4824bb33ccf335f756474cf21ab91318ee4a0dc7
parentbca541c364edc0f18e4edbb2f6918db5e5676ac8 (diff)
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[AArch64][6/14] Implement TARGET_OPTION_SAVE/TARGET_OPTION_RESTORE
* config/aarch64/aarch64.opt (explicit_tune_core): New TargetVariable. (explicit_arch): Likewise. (x_aarch64_isa_flags): Likewise. (mgeneral-regs-only): Mark as Save. (mfix-cortex-a53-835769): Likewise. (mcmodel=): Likewise. (mstrict-align): Likewise. (momit-leaf-frame-pointer): Likewise. (mtls-dialect): Likewise. (master=): Likewise. * config/aarch64/aarch64.h (ASM_DECLARE_FUNCTION_NAME): Define. (aarch64_isa_flags): Remove extern declaration. * config/aarch64/aarch64.c (aarch64_validate_mcpu): Return a bool to indicate success or failure. (aarch64_validate_march): Likewise. (aarch64_validate_mtune): Likewise. (aarch64_isa_flags): Delete. (aarch64_override_options_internal): Access opts->x_aarch64_isa_flags instead of aarch64_isa_flags. (aarch64_get_tune_cpu): New function. (aarch64_get_arch): Likewise. (aarch64_override_options): Use above and set up explicit_tune_core and explicit_arch. (aarch64_print_extension): Move earlier in file. Add isa_flags argument and use that instead of the global aarch64_isa_flags. (aarch64_option_save): New function. (aarch64_option_restore): Likewise. (aarch64_option_print): Likewise. (aarch64_declare_function_name): Likewise. (aarch64_start_file): Delete. (TARGET_ASM_FILE_START): Do not define. (TARGET_OPTION_RESTORE, TARGET_OPTION_PRINT): Define. * config/aarch64/aarch64-protos.h (aarch64_declare_function_name): Declare prototype. From-SVN: r226558
-rw-r--r--gcc/ChangeLog37
-rw-r--r--gcc/config/aarch64/aarch64-protos.h1
-rw-r--r--gcc/config/aarch64/aarch64.c233
-rw-r--r--gcc/config/aarch64/aarch64.h6
-rw-r--r--gcc/config/aarch64/aarch64.opt24
5 files changed, 242 insertions, 59 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 284547c..985d7df 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,42 @@
2015-08-04 Kyrylo Tkachov <kyrylo.tkachov@arm.com>
+ * config/aarch64/aarch64.opt (explicit_tune_core): New TargetVariable.
+ (explicit_arch): Likewise.
+ (x_aarch64_isa_flags): Likewise.
+ (mgeneral-regs-only): Mark as Save.
+ (mfix-cortex-a53-835769): Likewise.
+ (mcmodel=): Likewise.
+ (mstrict-align): Likewise.
+ (momit-leaf-frame-pointer): Likewise.
+ (mtls-dialect): Likewise.
+ (master=): Likewise.
+ * config/aarch64/aarch64.h (ASM_DECLARE_FUNCTION_NAME): Define.
+ (aarch64_isa_flags): Remove extern declaration.
+ * config/aarch64/aarch64.c (aarch64_validate_mcpu): Return a bool
+ to indicate success or failure.
+ (aarch64_validate_march): Likewise.
+ (aarch64_validate_mtune): Likewise.
+ (aarch64_isa_flags): Delete.
+ (aarch64_override_options_internal): Access opts->x_aarch64_isa_flags
+ instead of aarch64_isa_flags.
+ (aarch64_get_tune_cpu): New function.
+ (aarch64_get_arch): Likewise.
+ (aarch64_override_options): Use above and set up explicit_tune_core
+ and explicit_arch.
+ (aarch64_print_extension): Move earlier in file. Add isa_flags
+ argument and use that instead of the global aarch64_isa_flags.
+ (aarch64_option_save): New function.
+ (aarch64_option_restore): Likewise.
+ (aarch64_option_print): Likewise.
+ (aarch64_declare_function_name): Likewise.
+ (aarch64_start_file): Delete.
+ (TARGET_ASM_FILE_START): Do not define.
+ (TARGET_OPTION_RESTORE, TARGET_OPTION_PRINT): Define.
+ * config/aarch64/aarch64-protos.h (aarch64_declare_function_name):
+ Declare prototype.
+
+2015-08-04 Kyrylo Tkachov <kyrylo.tkachov@arm.com>
+
* config/aarch64/aarch64.opt (momit-leaf-frame-pointer): Initialize
flag_omit_leaf_frame_pointer to 2.
diff --git a/gcc/config/aarch64/aarch64-protos.h b/gcc/config/aarch64/aarch64-protos.h
index e4f5b00..fc1cec7 100644
--- a/gcc/config/aarch64/aarch64-protos.h
+++ b/gcc/config/aarch64/aarch64-protos.h
@@ -255,6 +255,7 @@ bool aarch64_gimple_fold_builtin (gimple_stmt_iterator *);
bool aarch64_is_extend_from_extract (machine_mode, rtx, rtx);
bool aarch64_is_long_call_p (rtx);
bool aarch64_label_mentioned_p (rtx);
+void aarch64_declare_function_name (FILE *, const char*, tree);
bool aarch64_legitimate_pic_operand_p (rtx);
bool aarch64_modes_tieable_p (machine_mode mode1,
machine_mode mode2);
diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index 3cd2927..caf50ea 100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -158,9 +158,6 @@ unsigned aarch64_architecture_version;
/* The processor for which instructions should be scheduled. */
enum aarch64_processor aarch64_tune = cortexa53;
-/* Mask to specify which instructions we are allowed to generate. */
-unsigned long aarch64_isa_flags = 0;
-
/* Mask to specify which instruction scheduling options should be used. */
unsigned long aarch64_tune_flags = 0;
@@ -531,8 +528,8 @@ static const struct processor all_cores[] =
};
-/* Target specification. These are populated as commandline arguments
- are processed, or NULL if not specified. */
+/* Target specification. These are populated by the -march, -mtune, -mcpu
+ handling code or by target attributes. */
static const struct processor *selected_arch;
static const struct processor *selected_cpu;
static const struct processor *selected_tune;
@@ -7552,7 +7549,7 @@ aarch64_override_options_internal (struct gcc_options *opts)
/* aarch64_parse_extension takes char* rather than const char* because
it is usually called from within other parsing functions. */
char tmp_str[] = "+nofp";
- aarch64_parse_extension (tmp_str, &aarch64_isa_flags);
+ aarch64_parse_extension (tmp_str, &opts->x_aarch64_isa_flags);
}
initialize_aarch64_code_model (opts);
@@ -7562,9 +7559,10 @@ aarch64_override_options_internal (struct gcc_options *opts)
/* Validate a command-line -mcpu option. Parse the cpu and extensions (if any)
specified in STR and throw errors if appropriate. Put the results if
- they are valid in RES and ISA_FLAGS. */
+ they are valid in RES and ISA_FLAGS. Return whether the option is
+ valid. */
-static void
+static bool
aarch64_validate_mcpu (const char *str, const struct processor **res,
unsigned long *isa_flags)
{
@@ -7572,7 +7570,7 @@ aarch64_validate_mcpu (const char *str, const struct processor **res,
= aarch64_parse_cpu (str, res, isa_flags);
if (parse_res == AARCH64_PARSE_OK)
- return;
+ return true;
switch (parse_res)
{
@@ -7588,13 +7586,16 @@ aarch64_validate_mcpu (const char *str, const struct processor **res,
default:
gcc_unreachable ();
}
+
+ return false;
}
/* Validate a command-line -march option. Parse the arch and extensions
(if any) specified in STR and throw errors if appropriate. Put the
- results, if they are valid, in RES and ISA_FLAGS. */
+ results, if they are valid, in RES and ISA_FLAGS. Return whether the
+ option is valid. */
-static void
+static bool
aarch64_validate_march (const char *str, const struct processor **res,
unsigned long *isa_flags)
{
@@ -7602,7 +7603,7 @@ aarch64_validate_march (const char *str, const struct processor **res,
= aarch64_parse_arch (str, res, isa_flags);
if (parse_res == AARCH64_PARSE_OK)
- return;
+ return true;
switch (parse_res)
{
@@ -7618,20 +7619,23 @@ aarch64_validate_march (const char *str, const struct processor **res,
default:
gcc_unreachable ();
}
+
+ return false;
}
/* Validate a command-line -mtune option. Parse the cpu
specified in STR and throw errors if appropriate. Put the
- result, if it is valid, in RES. */
+ result, if it is valid, in RES. Return whether the option is
+ valid. */
-static void
+static bool
aarch64_validate_mtune (const char *str, const struct processor **res)
{
enum aarch64_parse_opt_result parse_res
= aarch64_parse_tune (str, res);
if (parse_res == AARCH64_PARSE_OK)
- return;
+ return true;
switch (parse_res)
{
@@ -7644,6 +7648,38 @@ aarch64_validate_mtune (const char *str, const struct processor **res)
default:
gcc_unreachable ();
}
+ return false;
+}
+
+/* Return the CPU corresponding to the enum CPU.
+ If it doesn't specify a cpu, return the default. */
+
+static const struct processor *
+aarch64_get_tune_cpu (enum aarch64_processor cpu)
+{
+ if (cpu != aarch64_none)
+ return &all_cores[cpu];
+
+ /* The & 0x3f is to extract the bottom 6 bits that encode the
+ default cpu as selected by the --with-cpu GCC configure option
+ in config.gcc.
+ ???: The whole TARGET_CPU_DEFAULT and AARCH64_CPU_DEFAULT_FLAGS
+ flags mechanism should be reworked to make it more sane. */
+ return &all_cores[TARGET_CPU_DEFAULT & 0x3f];
+}
+
+/* Return the architecture corresponding to the enum ARCH.
+ If it doesn't specify a valid architecture, return the default. */
+
+static const struct processor *
+aarch64_get_arch (enum aarch64_arch arch)
+{
+ if (arch != aarch64_no_arch)
+ return &all_architectures[arch];
+
+ const struct processor *cpu = &all_cores[TARGET_CPU_DEFAULT & 0x3f];
+
+ return &all_architectures[cpu->arch];
}
/* Implement TARGET_OPTION_OVERRIDE. This is called once in the beginning
@@ -7660,6 +7696,10 @@ aarch64_override_options (void)
unsigned long arch_isa = 0;
aarch64_isa_flags = 0;
+ bool valid_cpu = true;
+ bool valid_tune = true;
+ bool valid_arch = true;
+
selected_cpu = NULL;
selected_arch = NULL;
selected_tune = NULL;
@@ -7668,13 +7708,15 @@ aarch64_override_options (void)
If either of -march or -mtune is given, they override their
respective component of -mcpu. */
if (aarch64_cpu_string)
- aarch64_validate_mcpu (aarch64_cpu_string, &selected_cpu, &cpu_isa);
+ valid_cpu = aarch64_validate_mcpu (aarch64_cpu_string, &selected_cpu,
+ &cpu_isa);
if (aarch64_arch_string)
- aarch64_validate_march (aarch64_arch_string, &selected_arch, &arch_isa);
+ valid_arch = aarch64_validate_march (aarch64_arch_string, &selected_arch,
+ &arch_isa);
if (aarch64_tune_string)
- aarch64_validate_mtune (aarch64_tune_string, &selected_tune);
+ valid_tune = aarch64_validate_mtune (aarch64_tune_string, &selected_tune);
/* If the user did not specify a processor, choose the default
one for them. This will be the CPU set during configuration using
@@ -7685,12 +7727,17 @@ aarch64_override_options (void)
{
selected_cpu = &all_cores[selected_arch->ident];
aarch64_isa_flags = arch_isa;
+ explicit_arch = selected_arch->arch;
}
else
{
- selected_cpu = &all_cores[TARGET_CPU_DEFAULT & 0x3f];
+ /* Get default configure-time CPU. */
+ selected_cpu = aarch64_get_tune_cpu (aarch64_none);
aarch64_isa_flags = TARGET_CPU_DEFAULT >> 6;
}
+
+ if (selected_tune)
+ explicit_tune_core = selected_tune->ident;
}
/* If both -mcpu and -march are specified check that they are architecturally
compatible, warn if they're not and prefer the -march ISA flags. */
@@ -7703,11 +7750,19 @@ aarch64_override_options (void)
selected_arch->name);
}
aarch64_isa_flags = arch_isa;
+ explicit_arch = selected_arch->arch;
+ explicit_tune_core = selected_tune ? selected_tune->ident
+ : selected_cpu->ident;
}
else
{
/* -mcpu but no -march. */
aarch64_isa_flags = cpu_isa;
+ explicit_tune_core = selected_tune ? selected_tune->ident
+ : selected_cpu->ident;
+ gcc_assert (selected_cpu);
+ selected_arch = &all_architectures[selected_cpu->arch];
+ explicit_arch = selected_arch->arch;
}
/* Set the arch as well as we will need it when outputing
@@ -7728,6 +7783,15 @@ aarch64_override_options (void)
error ("Assembler does not support -mabi=ilp32");
#endif
+ /* Make sure we properly set up the explicit options. */
+ if ((aarch64_cpu_string && valid_cpu)
+ || (aarch64_tune_string && valid_tune))
+ gcc_assert (explicit_tune_core != aarch64_none);
+
+ if ((aarch64_cpu_string && valid_cpu)
+ || (aarch64_arch_string && valid_arch))
+ gcc_assert (explicit_arch != aarch64_no_arch);
+
aarch64_build_bitmask_table ();
aarch64_override_options_internal (&global_options);
@@ -7794,6 +7858,59 @@ initialize_aarch64_code_model (struct gcc_options *opts)
aarch64_cmodel = opts->x_aarch64_cmodel_var;
}
+/* Print to F the architecture features specified by ISA_FLAGS. */
+
+static void
+aarch64_print_extension (FILE *f, unsigned long isa_flags)
+{
+ const struct aarch64_option_extension *opt = NULL;
+
+ for (opt = all_extensions; opt->name != NULL; opt++)
+ if ((isa_flags & opt->flags_on) == opt->flags_on)
+ asm_fprintf (f, "+%s", opt->name);
+
+ asm_fprintf (f, "\n");
+}
+
+/* Implement TARGET_OPTION_SAVE. */
+
+static void
+aarch64_option_save (struct cl_target_option *ptr, struct gcc_options *opts)
+{
+ ptr->x_aarch64_override_tune_string = opts->x_aarch64_override_tune_string;
+}
+
+/* Implements TARGET_OPTION_RESTORE. Restore the backend codegen decisions
+ using the information saved in PTR. */
+
+static void
+aarch64_option_restore (struct gcc_options *opts, struct cl_target_option *ptr)
+{
+ opts->x_explicit_tune_core = ptr->x_explicit_tune_core;
+ selected_tune = aarch64_get_tune_cpu (ptr->x_explicit_tune_core);
+ opts->x_explicit_arch = ptr->x_explicit_arch;
+ selected_arch = aarch64_get_arch (ptr->x_explicit_arch);
+ opts->x_aarch64_override_tune_string = ptr->x_aarch64_override_tune_string;
+
+ aarch64_override_options_internal (opts);
+}
+
+/* Implement TARGET_OPTION_PRINT. */
+
+static void
+aarch64_option_print (FILE *file, int indent, struct cl_target_option *ptr)
+{
+ const struct processor *cpu
+ = aarch64_get_tune_cpu (ptr->x_explicit_tune_core);
+ unsigned long isa_flags = ptr->x_aarch64_isa_flags;
+ const struct processor *arch = aarch64_get_arch (ptr->x_explicit_arch);
+
+ fprintf (file, "%*sselected tune = %s\n", indent, "", cpu->name);
+ fprintf (file, "%*sselected arch = %s", indent, "", arch->name);
+ aarch64_print_extension (file, isa_flags);
+}
+
+
/* Return true if SYMBOL_REF X binds locally. */
static bool
@@ -9805,6 +9922,42 @@ aarch64_asm_preferred_eh_data_format (int code ATTRIBUTE_UNUSED, int global)
return (global ? DW_EH_PE_indirect : 0) | DW_EH_PE_pcrel | type;
}
+/* Implement ASM_DECLARE_FUNCTION_NAME. Output the ISA features used
+ by the function fndecl. */
+
+void
+aarch64_declare_function_name (FILE *stream, const char* name,
+ tree fndecl)
+{
+ tree target_parts = DECL_FUNCTION_SPECIFIC_TARGET (fndecl);
+
+ struct cl_target_option *targ_options;
+ if (target_parts)
+ targ_options = TREE_TARGET_OPTION (target_parts);
+ else
+ targ_options = TREE_TARGET_OPTION (target_option_current_node);
+ gcc_assert (targ_options);
+
+ const struct processor *this_arch
+ = aarch64_get_arch (targ_options->x_explicit_arch);
+
+ asm_fprintf (asm_out_file, "\t.arch %s", this_arch->name);
+ aarch64_print_extension (asm_out_file, targ_options->x_aarch64_isa_flags);
+
+ /* Print the cpu name we're tuning for in the comments, might be
+ useful to readers of the generated asm. */
+
+ const struct processor *this_tune
+ = aarch64_get_tune_cpu (targ_options->x_explicit_tune_core);
+
+ asm_fprintf (asm_out_file, "\t" ASM_COMMENT_START ".tune %s\n",
+ this_tune->name);
+
+ /* Don't forget the type directive for ELF. */
+ ASM_OUTPUT_TYPE_DIRECTIVE (stream, name, "function");
+ ASM_OUTPUT_LABEL (stream, name);
+}
+
/* Emit load exclusive. */
static void
@@ -10086,36 +10239,6 @@ aarch64_split_atomic_op (enum rtx_code code, rtx old_out, rtx new_out, rtx mem,
}
static void
-aarch64_print_extension (void)
-{
- const struct aarch64_option_extension *opt = NULL;
-
- for (opt = all_extensions; opt->name != NULL; opt++)
- if ((aarch64_isa_flags & opt->flags_on) == opt->flags_on)
- asm_fprintf (asm_out_file, "+%s", opt->name);
-
- asm_fprintf (asm_out_file, "\n");
-}
-
-static void
-aarch64_start_file (void)
-{
- if (selected_arch)
- {
- asm_fprintf (asm_out_file, "\t.arch %s", selected_arch->name);
- aarch64_print_extension ();
- }
- else if (selected_cpu)
- {
- const char *truncated_name
- = aarch64_rewrite_selected_cpu (selected_cpu->name);
- asm_fprintf (asm_out_file, "\t.cpu %s", truncated_name);
- aarch64_print_extension ();
- }
- default_file_start();
-}
-
-static void
aarch64_init_libfuncs (void)
{
/* Half-precision float operations. The compiler handles all operations
@@ -12174,9 +12297,6 @@ aarch64_promoted_type (const_tree t)
#define TARGET_ASM_CAN_OUTPUT_MI_THUNK \
hook_bool_const_tree_hwi_hwi_const_tree_true
-#undef TARGET_ASM_FILE_START
-#define TARGET_ASM_FILE_START aarch64_start_file
-
#undef TARGET_ASM_OUTPUT_MI_THUNK
#define TARGET_ASM_OUTPUT_MI_THUNK aarch64_output_mi_thunk
@@ -12296,6 +12416,15 @@ aarch64_promoted_type (const_tree t)
#define TARGET_OVERRIDE_OPTIONS_AFTER_CHANGE \
aarch64_override_options_after_change
+#undef TARGET_OPTION_SAVE
+#define TARGET_OPTION_SAVE aarch64_option_save
+
+#undef TARGET_OPTION_RESTORE
+#define TARGET_OPTION_RESTORE aarch64_option_restore
+
+#undef TARGET_OPTION_PRINT
+#define TARGET_OPTION_PRINT aarch64_option_print
+
#undef TARGET_PASS_BY_REFERENCE
#define TARGET_PASS_BY_REFERENCE aarch64_pass_by_reference
diff --git a/gcc/config/aarch64/aarch64.h b/gcc/config/aarch64/aarch64.h
index 1f8f52c..9333bdc 100644
--- a/gcc/config/aarch64/aarch64.h
+++ b/gcc/config/aarch64/aarch64.h
@@ -223,7 +223,7 @@ extern unsigned aarch64_architecture_version;
| AARCH64_FL_LOR | AARCH64_FL_RDMA)
/* Macros to test ISA flags. */
-extern unsigned long aarch64_isa_flags;
+
#define AARCH64_ISA_CRC (aarch64_isa_flags & AARCH64_FL_CRC)
#define AARCH64_ISA_CRYPTO (aarch64_isa_flags & AARCH64_FL_CRYPTO)
#define AARCH64_ISA_FP (aarch64_isa_flags & AARCH64_FL_FP)
@@ -438,6 +438,10 @@ extern unsigned long aarch64_isa_flags;
#define ASM_PREFERRED_EH_DATA_FORMAT(CODE, GLOBAL) \
aarch64_asm_preferred_eh_data_format ((CODE), (GLOBAL))
+/* Output the assembly strings we want to add to a function definition. */
+#define ASM_DECLARE_FUNCTION_NAME(STR, NAME, DECL) \
+ aarch64_declare_function_name (STR, NAME, DECL)
+
/* The register that holds the return address in exception handlers. */
#define AARCH64_EH_STACKADJ_REGNUM (R0_REGNUM + 4)
#define EH_RETURN_STACKADJ_RTX gen_rtx_REG (Pmode, AARCH64_EH_STACKADJ_REGNUM)
diff --git a/gcc/config/aarch64/aarch64.opt b/gcc/config/aarch64/aarch64.opt
index e29d606..37c2c50 100644
--- a/gcc/config/aarch64/aarch64.opt
+++ b/gcc/config/aarch64/aarch64.opt
@@ -21,6 +21,18 @@
HeaderInclude
config/aarch64/aarch64-opts.h
+TargetVariable
+enum aarch64_processor explicit_tune_core = aarch64_none
+
+TargetVariable
+enum aarch64_arch explicit_arch = aarch64_no_arch
+
+TargetSave
+const char *x_aarch64_override_tune_string
+
+TargetVariable
+unsigned long aarch64_isa_flags = 0
+
; The TLS dialect names to use with -mtls-dialect.
Enum
@@ -53,11 +65,11 @@ Target Report RejectNegative Mask(BIG_END)
Assume target CPU is configured as big endian
mgeneral-regs-only
-Target Report RejectNegative Mask(GENERAL_REGS_ONLY)
+Target Report RejectNegative Mask(GENERAL_REGS_ONLY) Save
Generate code which uses only the general registers
mfix-cortex-a53-835769
-Target Report Var(aarch64_fix_a53_err835769) Init(2)
+Target Report Var(aarch64_fix_a53_err835769) Init(2) Save
Workaround for ARM Cortex-A53 Erratum number 835769
mfix-cortex-a53-843419
@@ -69,19 +81,19 @@ Target Report RejectNegative InverseMask(BIG_END)
Assume target CPU is configured as little endian
mcmodel=
-Target RejectNegative Joined Enum(cmodel) Var(aarch64_cmodel_var) Init(AARCH64_CMODEL_SMALL)
+Target RejectNegative Joined Enum(cmodel) Var(aarch64_cmodel_var) Init(AARCH64_CMODEL_SMALL) Save
Specify the code model
mstrict-align
-Target Report RejectNegative Mask(STRICT_ALIGN)
+Target Report RejectNegative Mask(STRICT_ALIGN) Save
Don't assume that unaligned accesses are handled by the system
momit-leaf-frame-pointer
-Target Report Save Var(flag_omit_leaf_frame_pointer) Init(2)
+Target Report Var(flag_omit_leaf_frame_pointer) Init(2) Save
Omit the frame pointer in leaf functions
mtls-dialect=
-Target RejectNegative Joined Enum(tls_type) Var(aarch64_tls_dialect) Init(TLS_DESCRIPTORS)
+Target RejectNegative Joined Enum(tls_type) Var(aarch64_tls_dialect) Init(TLS_DESCRIPTORS) Save
Specify TLS dialect
march=