| Message ID | 000001d0548a$789a1bd0$69ce5370$@arm.com |
|---|---|
| State | New |
| Headers | show |
> On Mar 2, 2015, at 4:44 AM, Terry Guo <terry.guo@arm.com> wrote: > > Hi there, > > If target mode isn't specified via either gcc configuration option > --with-mode or command line, this patch intends to improve gcc driver to > automatically add option -mthumb for thumb-only target. Tested with gcc > regression test for various arm targets, no regression. Is it OK? > > BR, > Terry > > gcc/ChangeLog: > > 2015-03-02 Terry Guo <terry.guo@arm.com> > > * common/config/arm/arm-common.c (arm_is_target_thumb_only): New > function. > * config/arm/arm-protos.h (FL_ Macros): Move to ... > * config/arm/arm-opts.h (FL_ Macros): ... here. > (struct arm_arch_core_flag): New struct. > (arm_arch_core_flags): New array for arch/core and flag map. > * config/arm/arm.h (MODE_SET_SPEC_FUNCTIONS): Define new SPEC > function. > (EXTRA_SPEC_FUNCTIONS): Include new SPEC function. > (MODE_SET_SPECS): New SPEC. > (DRIVER_SELF_SPECS): Include new SPEC.<gcc-mthumb-option-v5.txt> Did you consider approach of implementing this purely inside cc1 rather than driver? We do not seem to need to pass -mthumb to assembler or linker since those will pick up ARM-ness / Thumb-ness from function annotations. Therefore we need to handle -marm / -mthumb for cc1 only. What am I missing? Also, what's the significance of moving FL_* flags to arm-opts.h? If you had to separate FL_* definitions from the rest of arm-protos.h, then a new dedicated file (e.g., arm-fl.h) would be a better choice for new home of FL_* definitions. Thank you, -- Maxim Kuvyrkov www.linaro.org
On Mon, Mar 02, 2015 at 01:08:13PM +0000, Maxim Kuvyrkov wrote: > > On Mar 2, 2015, at 4:44 AM, Terry Guo <terry.guo@arm.com> wrote: > > > > Hi there, > > > > If target mode isn't specified via either gcc configuration option > > --with-mode or command line, this patch intends to improve gcc driver to > > automatically add option -mthumb for thumb-only target. Tested with gcc > > regression test for various arm targets, no regression. Is it OK? > > > > BR, > > Terry > > > > gcc/ChangeLog: > > > > 2015-03-02 Terry Guo <terry.guo@arm.com> > > > > * common/config/arm/arm-common.c (arm_is_target_thumb_only): New > > function. > > * config/arm/arm-protos.h (FL_ Macros): Move to ... > > * config/arm/arm-opts.h (FL_ Macros): ... here. > > (struct arm_arch_core_flag): New struct. > > (arm_arch_core_flags): New array for arch/core and flag map. > > * config/arm/arm.h (MODE_SET_SPEC_FUNCTIONS): Define new SPEC > > function. > > (EXTRA_SPEC_FUNCTIONS): Include new SPEC function. > > (MODE_SET_SPECS): New SPEC. > > (DRIVER_SELF_SPECS): Include new SPEC.<gcc-mthumb-option-v5.txt> > > Did you consider approach of implementing this purely inside cc1 rather than driver? > > We do not seem to need to pass -mthumb to assembler or linker since those > will pick up ARM-ness / Thumb-ness from function annotations. Therefore we > need to handle -marm / -mthumb for cc1 only. What am I missing? I recently had a similar argument with myself regarding the usefulness of rewriting -mcpu values in the driver before handing them off the assembler (as we do for big.LITTLE systems), we could just rely on the .arch directives in the assembler files. The problem with this argument, and the one you make here, is that it doesn't cover users driving the assembler with a GCC command to assemble hand-rolled files without directives. i.e. gcc foo.s bar.c -mthumb -mcpu=cortex-a57.cortex-a53 Should have the effect when assembling foo.s of enforcing thumb mode, and permitting ARMv8-A instructions, regardless whether foo.s explicitly enables these through directives. Cheers, James
> -----Original Message----- > From: gcc-patches-owner@gcc.gnu.org [mailto:gcc-patches- > owner@gcc.gnu.org] On Behalf Of James Greenhalgh > Sent: 02 March 2015 13:28 > To: Maxim Kuvyrkov > Cc: Terry Guo; gcc-patches@gcc.gnu.org; Ramana Radhakrishnan; Richard > Earnshaw > Subject: Re: [PATCH][ARM]Automatically add -mthumb for thumb-only > target when mode isn't specified > > On Mon, Mar 02, 2015 at 01:08:13PM +0000, Maxim Kuvyrkov wrote: > > > On Mar 2, 2015, at 4:44 AM, Terry Guo <terry.guo@arm.com> wrote: > > > > > > Hi there, > > > > > > If target mode isn't specified via either gcc configuration option > > > --with-mode or command line, this patch intends to improve gcc > > > driver to automatically add option -mthumb for thumb-only target. > > > Tested with gcc regression test for various arm targets, no regression. Is it > OK? FWIW, I had this annoyance that the patch tries to fix as well and filed a PR for it: PR target/64802 Kyrill > > > > > > BR, > > > Terry > > > > > > gcc/ChangeLog: > > > > > > 2015-03-02 Terry Guo <terry.guo@arm.com> > > > > > > * common/config/arm/arm-common.c (arm_is_target_thumb_only): > > > New function. > > > * config/arm/arm-protos.h (FL_ Macros): Move to ... > > > * config/arm/arm-opts.h (FL_ Macros): ... here. > > > (struct arm_arch_core_flag): New struct. > > > (arm_arch_core_flags): New array for arch/core and flag map. > > > * config/arm/arm.h (MODE_SET_SPEC_FUNCTIONS): Define new > SPEC > > > function. > > > (EXTRA_SPEC_FUNCTIONS): Include new SPEC function. > > > (MODE_SET_SPECS): New SPEC. > > > (DRIVER_SELF_SPECS): Include new > > > SPEC.<gcc-mthumb-option-v5.txt> > > > > Did you consider approach of implementing this purely inside cc1 rather > than driver? > > > > We do not seem to need to pass -mthumb to assembler or linker since > > those will pick up ARM-ness / Thumb-ness from function annotations. > > Therefore we need to handle -marm / -mthumb for cc1 only. What am I > missing? > > I recently had a similar argument with myself regarding the usefulness of > rewriting -mcpu values in the driver before handing them off the assembler > (as we do for big.LITTLE systems), we could just rely on the .arch directives in > the assembler files. > > The problem with this argument, and the one you make here, is that it > doesn't cover users driving the assembler with a GCC command to assemble > hand-rolled files without directives. i.e. > > gcc foo.s bar.c -mthumb -mcpu=cortex-a57.cortex-a53 > > Should have the effect when assembling foo.s of enforcing thumb mode, > and permitting ARMv8-A instructions, regardless whether foo.s explicitly > enables these through directives. > > Cheers, > James >
On Mon, Mar 2, 2015 at 9:08 PM, Maxim Kuvyrkov <maxim.kuvyrkov@linaro.org> wrote: >> On Mar 2, 2015, at 4:44 AM, Terry Guo <terry.guo@arm.com> wrote: >> >> Hi there, >> >> If target mode isn't specified via either gcc configuration option >> --with-mode or command line, this patch intends to improve gcc driver to >> automatically add option -mthumb for thumb-only target. Tested with gcc >> regression test for various arm targets, no regression. Is it OK? >> >> BR, >> Terry >> >> gcc/ChangeLog: >> >> 2015-03-02 Terry Guo <terry.guo@arm.com> >> >> * common/config/arm/arm-common.c (arm_is_target_thumb_only): New >> function. >> * config/arm/arm-protos.h (FL_ Macros): Move to ... >> * config/arm/arm-opts.h (FL_ Macros): ... here. >> (struct arm_arch_core_flag): New struct. >> (arm_arch_core_flags): New array for arch/core and flag map. >> * config/arm/arm.h (MODE_SET_SPEC_FUNCTIONS): Define new SPEC >> function. >> (EXTRA_SPEC_FUNCTIONS): Include new SPEC function. >> (MODE_SET_SPECS): New SPEC. >> (DRIVER_SELF_SPECS): Include new SPEC.<gcc-mthumb-option-v5.txt> > > Did you consider approach of implementing this purely inside cc1 rather than driver? > > We do not seem to need to pass -mthumb to assembler or linker since those will pick up ARM-ness / Thumb-ness from function annotations. Therefore we need to handle -marm / -mthumb for cc1 only. What am I missing? > The way GCC uses to find multitlib prevents us from doing this via cc1. The target options should be properly constructed for gcc driver to decide multilib path, which happens before cc1. For example, for command line "arm-nonee-abi-gcc -mcpu=cortex-m3 -o hello.axf hello.c", we need to figure out that -mthumb should be added inside the gcc driver, otherwise such command line works like "arm-nonee-abi-gcc -marm -mcpu=cortex-m3 -o hello.axf hello.c" and the arm mode multilib will be linked. Thus we have to do this in gcc driver rather than cc1. > Also, what's the significance of moving FL_* flags to arm-opts.h? If you had to separate FL_* definitions from the rest of arm-protos.h, then a new dedicated file (e.g., arm-fl.h) would be a better choice for new home of FL_* definitions. > I set up an arch/core<->flags map array for gcc driver to figure out whether the target is thumb-only. Those FL_* flags are needed for this map array. The arm-opts.h is used to share back end information with gcc driver. Normally we tend to minimize such information. That's why I just moved those FL_* flags rather than simply including the header file which has FL_* flags. But maybe it is a good idea to save FL_* into a separate file. I will try. BR, Terry
On Mon, Mar 2, 2015 at 9:08 PM, Maxim Kuvyrkov <maxim.kuvyrkov@linaro.org> wrote: >> On Mar 2, 2015, at 4:44 AM, Terry Guo <terry.guo@arm.com> wrote: >> >> Hi there, >> >> If target mode isn't specified via either gcc configuration option >> --with-mode or command line, this patch intends to improve gcc driver to >> automatically add option -mthumb for thumb-only target. Tested with gcc >> regression test for various arm targets, no regression. Is it OK? >> >> BR, >> Terry >> >> gcc/ChangeLog: >> >> 2015-03-02 Terry Guo <terry.guo@arm.com> >> >> * common/config/arm/arm-common.c (arm_is_target_thumb_only): New >> function. >> * config/arm/arm-protos.h (FL_ Macros): Move to ... >> * config/arm/arm-opts.h (FL_ Macros): ... here. >> (struct arm_arch_core_flag): New struct. >> (arm_arch_core_flags): New array for arch/core and flag map. >> * config/arm/arm.h (MODE_SET_SPEC_FUNCTIONS): Define new SPEC >> function. >> (EXTRA_SPEC_FUNCTIONS): Include new SPEC function. >> (MODE_SET_SPECS): New SPEC. >> (DRIVER_SELF_SPECS): Include new SPEC.<gcc-mthumb-option-v5.txt> > > Did you consider approach of implementing this purely inside cc1 rather than driver? > > We do not seem to need to pass -mthumb to assembler or linker since those will pick up ARM-ness / Thumb-ness from function annotations. Therefore we need to handle -marm / -mthumb for cc1 only. What am I missing? > > Also, what's the significance of moving FL_* flags to arm-opts.h? If you had to separate FL_* definitions from the rest of arm-protos.h, then a new dedicated file (e.g., arm-fl.h) would be a better choice for new home of FL_* definitions. > Please find my answers in another email. The attached patch tries to follow your idea that puts those FL_* into separate file named arm-flags.h. Does it look good to you? BR, Terry
diff --git a/gcc/common/config/arm/arm-common.c b/gcc/common/config/arm/arm-common.c index 86673b7..e17ee03 100644 --- a/gcc/common/config/arm/arm-common.c +++ b/gcc/common/config/arm/arm-common.c @@ -97,6 +97,28 @@ arm_rewrite_mcpu (int argc, const char **argv) return arm_rewrite_selected_cpu (argv[argc - 1]); } +/* Called by driver to check whether the target denoted by current + command line options is thumb-only target. If -march present, + check the last -march option. If no -march, check the last -mcpu + option. */ +const char * +arm_is_target_thumb_only (int argc, const char **argv) +{ + unsigned int opt; + + if (argc) + { + for (opt = 0; opt < (ARRAY_SIZE (arm_arch_core_flags) - 1); opt++) + if ((strcmp (argv[argc - 1], arm_arch_core_flags[opt].name) == 0) + && ((arm_arch_core_flags[opt].flags & FL_NOTM) == 0)) + return "-mthumb"; + + return NULL; + } + else + return NULL; +} + #undef ARM_CPU_NAME_LENGTH diff --git a/gcc/config/arm/arm-opts.h b/gcc/config/arm/arm-opts.h index 039e333..222d20e 100644 --- a/gcc/config/arm/arm-opts.h +++ b/gcc/config/arm/arm-opts.h @@ -77,4 +77,93 @@ enum arm_tls_type { TLS_GNU, TLS_GNU2 }; + +/* Flags used to identify the presence of processor capabilities. */ + +/* Bit values used to identify processor capabilities. */ +#define FL_CO_PROC (1 << 0) /* Has external co-processor bus */ +#define FL_ARCH3M (1 << 1) /* Extended multiply */ +#define FL_MODE26 (1 << 2) /* 26-bit mode support */ +#define FL_MODE32 (1 << 3) /* 32-bit mode support */ +#define FL_ARCH4 (1 << 4) /* Architecture rel 4 */ +#define FL_ARCH5 (1 << 5) /* Architecture rel 5 */ +#define FL_THUMB (1 << 6) /* Thumb aware */ +#define FL_LDSCHED (1 << 7) /* Load scheduling necessary */ +#define FL_STRONG (1 << 8) /* StrongARM */ +#define FL_ARCH5E (1 << 9) /* DSP extensions to v5 */ +#define FL_XSCALE (1 << 10) /* XScale */ +/* spare (1 << 11) */ +#define FL_ARCH6 (1 << 12) /* Architecture rel 6. Adds + media instructions. */ +#define FL_VFPV2 (1 << 13) /* Vector Floating Point V2. */ +#define FL_WBUF (1 << 14) /* Schedule for write buffer ops. + Note: ARM6 & 7 derivatives only. */ +#define FL_ARCH6K (1 << 15) /* Architecture rel 6 K extensions. */ +#define FL_THUMB2 (1 << 16) /* Thumb-2. */ +#define FL_NOTM (1 << 17) /* Instructions not present in the 'M' + profile. */ +#define FL_THUMB_DIV (1 << 18) /* Hardware divide (Thumb mode). */ +#define FL_VFPV3 (1 << 19) /* Vector Floating Point V3. */ +#define FL_NEON (1 << 20) /* Neon instructions. */ +#define FL_ARCH7EM (1 << 21) /* Instructions present in the ARMv7E-M + architecture. */ +#define FL_ARCH7 (1 << 22) /* Architecture 7. */ +#define FL_ARM_DIV (1 << 23) /* Hardware divide (ARM mode). */ +#define FL_ARCH8 (1 << 24) /* Architecture 8. */ +#define FL_CRC32 (1 << 25) /* ARMv8 CRC32 instructions. */ + +#define FL_SMALLMUL (1 << 26) /* Small multiply supported. */ + +#define FL_IWMMXT (1 << 29) /* XScale v2 or "Intel Wireless MMX technology". */ +#define FL_IWMMXT2 (1 << 30) /* "Intel Wireless MMX2 technology". */ + +/* Flags that only effect tuning, not available instructions. */ +#define FL_TUNE (FL_WBUF | FL_VFPV2 | FL_STRONG | FL_LDSCHED \ + | FL_CO_PROC) + +#define FL_FOR_ARCH2 FL_NOTM +#define FL_FOR_ARCH3 (FL_FOR_ARCH2 | FL_MODE32) +#define FL_FOR_ARCH3M (FL_FOR_ARCH3 | FL_ARCH3M) +#define FL_FOR_ARCH4 (FL_FOR_ARCH3M | FL_ARCH4) +#define FL_FOR_ARCH4T (FL_FOR_ARCH4 | FL_THUMB) +#define FL_FOR_ARCH5 (FL_FOR_ARCH4 | FL_ARCH5) +#define FL_FOR_ARCH5T (FL_FOR_ARCH5 | FL_THUMB) +#define FL_FOR_ARCH5E (FL_FOR_ARCH5 | FL_ARCH5E) +#define FL_FOR_ARCH5TE (FL_FOR_ARCH5E | FL_THUMB) +#define FL_FOR_ARCH5TEJ FL_FOR_ARCH5TE +#define FL_FOR_ARCH6 (FL_FOR_ARCH5TE | FL_ARCH6) +#define FL_FOR_ARCH6J FL_FOR_ARCH6 +#define FL_FOR_ARCH6K (FL_FOR_ARCH6 | FL_ARCH6K) +#define FL_FOR_ARCH6Z FL_FOR_ARCH6 +#define FL_FOR_ARCH6ZK FL_FOR_ARCH6K +#define FL_FOR_ARCH6T2 (FL_FOR_ARCH6 | FL_THUMB2) +#define FL_FOR_ARCH6M (FL_FOR_ARCH6 & ~FL_NOTM) +#define FL_FOR_ARCH7 ((FL_FOR_ARCH6T2 & ~FL_NOTM) | FL_ARCH7) +#define FL_FOR_ARCH7A (FL_FOR_ARCH7 | FL_NOTM | FL_ARCH6K) +#define FL_FOR_ARCH7VE (FL_FOR_ARCH7A | FL_THUMB_DIV | FL_ARM_DIV) +#define FL_FOR_ARCH7R (FL_FOR_ARCH7A | FL_THUMB_DIV) +#define FL_FOR_ARCH7M (FL_FOR_ARCH7 | FL_THUMB_DIV) +#define FL_FOR_ARCH7EM (FL_FOR_ARCH7M | FL_ARCH7EM) +#define FL_FOR_ARCH8A (FL_FOR_ARCH7VE | FL_ARCH8) + +struct arm_arch_core_flag +{ + const char *const name; + const unsigned long flags; +}; + +static const struct arm_arch_core_flag arm_arch_core_flags[] = +{ +#undef ARM_CORE +#define ARM_CORE(NAME, X, IDENT, ARCH, FLAGS, COSTS) \ + {NAME, FLAGS | FL_FOR_ARCH##ARCH}, +#include "arm-cores.def" +#undef ARM_CORE +#undef ARM_ARCH +#define ARM_ARCH(NAME, CORE, ARCH, FLAGS) \ + {NAME, FLAGS}, +#include "arm-arches.def" +#undef ARM_ARCH + {NULL, 0} +}; #endif diff --git a/gcc/config/arm/arm-protos.h b/gcc/config/arm/arm-protos.h index 307babb..ebb341b 100644 --- a/gcc/config/arm/arm-protos.h +++ b/gcc/config/arm/arm-protos.h @@ -325,74 +325,6 @@ extern const char *arm_rewrite_selected_cpu (const char *name); extern bool arm_is_constant_pool_ref (rtx); -/* Flags used to identify the presence of processor capabilities. */ - -/* Bit values used to identify processor capabilities. */ -#define FL_CO_PROC (1 << 0) /* Has external co-processor bus */ -#define FL_ARCH3M (1 << 1) /* Extended multiply */ -#define FL_MODE26 (1 << 2) /* 26-bit mode support */ -#define FL_MODE32 (1 << 3) /* 32-bit mode support */ -#define FL_ARCH4 (1 << 4) /* Architecture rel 4 */ -#define FL_ARCH5 (1 << 5) /* Architecture rel 5 */ -#define FL_THUMB (1 << 6) /* Thumb aware */ -#define FL_LDSCHED (1 << 7) /* Load scheduling necessary */ -#define FL_STRONG (1 << 8) /* StrongARM */ -#define FL_ARCH5E (1 << 9) /* DSP extensions to v5 */ -#define FL_XSCALE (1 << 10) /* XScale */ -/* spare (1 << 11) */ -#define FL_ARCH6 (1 << 12) /* Architecture rel 6. Adds - media instructions. */ -#define FL_VFPV2 (1 << 13) /* Vector Floating Point V2. */ -#define FL_WBUF (1 << 14) /* Schedule for write buffer ops. - Note: ARM6 & 7 derivatives only. */ -#define FL_ARCH6K (1 << 15) /* Architecture rel 6 K extensions. */ -#define FL_THUMB2 (1 << 16) /* Thumb-2. */ -#define FL_NOTM (1 << 17) /* Instructions not present in the 'M' - profile. */ -#define FL_THUMB_DIV (1 << 18) /* Hardware divide (Thumb mode). */ -#define FL_VFPV3 (1 << 19) /* Vector Floating Point V3. */ -#define FL_NEON (1 << 20) /* Neon instructions. */ -#define FL_ARCH7EM (1 << 21) /* Instructions present in the ARMv7E-M - architecture. */ -#define FL_ARCH7 (1 << 22) /* Architecture 7. */ -#define FL_ARM_DIV (1 << 23) /* Hardware divide (ARM mode). */ -#define FL_ARCH8 (1 << 24) /* Architecture 8. */ -#define FL_CRC32 (1 << 25) /* ARMv8 CRC32 instructions. */ - -#define FL_SMALLMUL (1 << 26) /* Small multiply supported. */ - -#define FL_IWMMXT (1 << 29) /* XScale v2 or "Intel Wireless MMX technology". */ -#define FL_IWMMXT2 (1 << 30) /* "Intel Wireless MMX2 technology". */ - -/* Flags that only effect tuning, not available instructions. */ -#define FL_TUNE (FL_WBUF | FL_VFPV2 | FL_STRONG | FL_LDSCHED \ - | FL_CO_PROC) - -#define FL_FOR_ARCH2 FL_NOTM -#define FL_FOR_ARCH3 (FL_FOR_ARCH2 | FL_MODE32) -#define FL_FOR_ARCH3M (FL_FOR_ARCH3 | FL_ARCH3M) -#define FL_FOR_ARCH4 (FL_FOR_ARCH3M | FL_ARCH4) -#define FL_FOR_ARCH4T (FL_FOR_ARCH4 | FL_THUMB) -#define FL_FOR_ARCH5 (FL_FOR_ARCH4 | FL_ARCH5) -#define FL_FOR_ARCH5T (FL_FOR_ARCH5 | FL_THUMB) -#define FL_FOR_ARCH5E (FL_FOR_ARCH5 | FL_ARCH5E) -#define FL_FOR_ARCH5TE (FL_FOR_ARCH5E | FL_THUMB) -#define FL_FOR_ARCH5TEJ FL_FOR_ARCH5TE -#define FL_FOR_ARCH6 (FL_FOR_ARCH5TE | FL_ARCH6) -#define FL_FOR_ARCH6J FL_FOR_ARCH6 -#define FL_FOR_ARCH6K (FL_FOR_ARCH6 | FL_ARCH6K) -#define FL_FOR_ARCH6Z FL_FOR_ARCH6 -#define FL_FOR_ARCH6ZK FL_FOR_ARCH6K -#define FL_FOR_ARCH6T2 (FL_FOR_ARCH6 | FL_THUMB2) -#define FL_FOR_ARCH6M (FL_FOR_ARCH6 & ~FL_NOTM) -#define FL_FOR_ARCH7 ((FL_FOR_ARCH6T2 & ~FL_NOTM) | FL_ARCH7) -#define FL_FOR_ARCH7A (FL_FOR_ARCH7 | FL_NOTM | FL_ARCH6K) -#define FL_FOR_ARCH7VE (FL_FOR_ARCH7A | FL_THUMB_DIV | FL_ARM_DIV) -#define FL_FOR_ARCH7R (FL_FOR_ARCH7A | FL_THUMB_DIV) -#define FL_FOR_ARCH7M (FL_FOR_ARCH7 | FL_THUMB_DIV) -#define FL_FOR_ARCH7EM (FL_FOR_ARCH7M | FL_ARCH7EM) -#define FL_FOR_ARCH8A (FL_FOR_ARCH7VE | FL_ARCH8) - /* The bits in this mask specify which instructions we are allowed to generate. */ extern unsigned long insn_flags; diff --git a/gcc/config/arm/arm.h b/gcc/config/arm/arm.h index 297dfe1..22b0f44 100644 --- a/gcc/config/arm/arm.h +++ b/gcc/config/arm/arm.h @@ -2388,13 +2388,18 @@ extern const char *arm_rewrite_mcpu (int argc, const char **argv); " :%{march=*:-march=%*}}" \ BIG_LITTLE_SPEC +extern const char *arm_is_target_thumb_only (int argc, const char **argv); +#define MODE_SET_SPEC_FUNCTIONS \ + { "target_mode_check", arm_is_target_thumb_only }, + /* -mcpu=native handling only makes sense with compiler running on an ARM chip. */ #if defined(__arm__) extern const char *host_detect_local_cpu (int argc, const char **argv); # define EXTRA_SPEC_FUNCTIONS \ { "local_cpu_detect", host_detect_local_cpu }, \ - BIG_LITTLE_CPU_SPEC_FUNCTIONS + BIG_LITTLE_CPU_SPEC_FUNCTIONS \ + MODE_SET_SPEC_FUNCTIONS # define MCPU_MTUNE_NATIVE_SPECS \ " %{march=native:%<march=native %:local_cpu_detect(arch)}" \ @@ -2402,9 +2407,19 @@ extern const char *host_detect_local_cpu (int argc, const char **argv); " %{mtune=native:%<mtune=native %:local_cpu_detect(tune)}" #else # define MCPU_MTUNE_NATIVE_SPECS "" -# define EXTRA_SPEC_FUNCTIONS BIG_LITTLE_CPU_SPEC_FUNCTIONS +# define EXTRA_SPEC_FUNCTIONS \ + BIG_LITTLE_CPU_SPEC_FUNCTIONS \ + MODE_SET_SPEC_FUNCTIONS #endif -#define DRIVER_SELF_SPECS MCPU_MTUNE_NATIVE_SPECS +/* Automatically add -mthumb for thumb-only target if mode isn't specified + via configuration option --with-mode and command line. + If -march present, we collect just -march options. Otherwise we + collect just -mcpu options. The last one of them will be used to + decide target mode. */ +#define MODE_SET_SPECS \ + " %{!marm:%{!mthumb:%:target_mode_check(%{march=*:%*;mcpu=*:%*})}}" + +#define DRIVER_SELF_SPECS MCPU_MTUNE_NATIVE_SPECS MODE_SET_SPECS #define TARGET_SUPPORTS_WIDE_INT 1 #endif /* ! GCC_ARM_H */
Hi there, If target mode isn't specified via either gcc configuration option --with-mode or command line, this patch intends to improve gcc driver to automatically add option -mthumb for thumb-only target. Tested with gcc regression test for various arm targets, no regression. Is it OK? BR, Terry gcc/ChangeLog: 2015-03-02 Terry Guo <terry.guo@arm.com> * common/config/arm/arm-common.c (arm_is_target_thumb_only): New function. * config/arm/arm-protos.h (FL_ Macros): Move to ... * config/arm/arm-opts.h (FL_ Macros): ... here. (struct arm_arch_core_flag): New struct. (arm_arch_core_flags): New array for arch/core and flag map. * config/arm/arm.h (MODE_SET_SPEC_FUNCTIONS): Define new SPEC function. (EXTRA_SPEC_FUNCTIONS): Include new SPEC function. (MODE_SET_SPECS): New SPEC. (DRIVER_SELF_SPECS): Include new SPEC.