| Message ID | 20231208055501.2916202-6-samuel.holland@sifive.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Unified cross-architecture kernel-mode FPU API | expand |
> +CFLAGS_REMOVE_neon1.o += $(CC_FLAGS_NO_FPU) > +CFLAGS_REMOVE_neon2.o += $(CC_FLAGS_NO_FPU) > +CFLAGS_REMOVE_neon4.o += $(CC_FLAGS_NO_FPU) > +CFLAGS_REMOVE_neon8.o += $(CC_FLAGS_NO_FPU) Btw, do we even really need the extra variables for compiler flags to remove? Don't gcc/clang options work so that if you add a no-prefixed version of the option later it transparently gets removed? Except for that: Reviewed-by: Christoph Hellwig <hch@lst.de>
On 2023-12-11 10:07 AM, Christoph Hellwig wrote: >> +CFLAGS_REMOVE_neon1.o += $(CC_FLAGS_NO_FPU) >> +CFLAGS_REMOVE_neon2.o += $(CC_FLAGS_NO_FPU) >> +CFLAGS_REMOVE_neon4.o += $(CC_FLAGS_NO_FPU) >> +CFLAGS_REMOVE_neon8.o += $(CC_FLAGS_NO_FPU) > > Btw, do we even really need the extra variables for compiler flags > to remove? Don't gcc/clang options work so that if you add a > no-prefixed version of the option later it transparently gets removed? Unfortunately, not all of the relevant options can be no-prefixed: $ cat float.c int main(void) { volatile float f = 123.456; return f / 10; } $ aarch64-linux-musl-gcc float.c $ aarch64-linux-musl-gcc -mgeneral-regs-only float.c float.c: In function 'main': float.c:1:33: error: '-mgeneral-regs-only' is incompatible with the use of floating-point types 1 | int main(void) { volatile float f = 123.456; return f / 10; } | ^ float.c:1:55: error: '-mgeneral-regs-only' is incompatible with the use of floating-point types 1 | int main(void) { volatile float f = 123.456; return f / 10; } | ~~^~~~ float.c:1:55: error: '-mgeneral-regs-only' is incompatible with the use of floating-point types float.c:1:55: error: '-mgeneral-regs-only' is incompatible with the use of floating-point types float.c:1:55: error: '-mgeneral-regs-only' is incompatible with the use of floating-point types float.c:1:55: error: '-mgeneral-regs-only' is incompatible with the use of floating-point types float.c:1:55: error: '-mgeneral-regs-only' is incompatible with the use of floating-point types float.c:1:55: error: '-mgeneral-regs-only' is incompatible with the use of floating-point types float.c:1:55: error: '-mgeneral-regs-only' is incompatible with the use of floating-point types float.c:1:55: error: '-mgeneral-regs-only' is incompatible with the use of floating-point types $ aarch64-linux-musl-gcc -mgeneral-regs-only -mno-general-regs-only float.c aarch64-linux-musl-gcc: error: unrecognized command-line option '-mno-general-regs-only'; did you mean '-mgeneral-regs-only'? $
On Mon, Dec 11, 2023 at 10:12:27AM -0600, Samuel Holland wrote: > On 2023-12-11 10:07 AM, Christoph Hellwig wrote: > > Unfortunately, not all of the relevant options can be no-prefixed: Ok. That is another good argument for having the obj-fpu += syntax I proposed. You might need help from the kbuild maintainers from that as trying to understand the kbuild magic isn't something I'd expect from a normal contributor (including myself..).
diff --git a/lib/raid6/Makefile b/lib/raid6/Makefile index 1c5420ff254e..309fea97efc6 100644 --- a/lib/raid6/Makefile +++ b/lib/raid6/Makefile @@ -33,25 +33,6 @@ CFLAGS_REMOVE_vpermxor8.o += -msoft-float endif endif -# The GCC option -ffreestanding is required in order to compile code containing -# ARM/NEON intrinsics in a non C99-compliant environment (such as the kernel) -ifeq ($(CONFIG_KERNEL_MODE_NEON),y) -NEON_FLAGS := -ffreestanding -# Enable <arm_neon.h> -NEON_FLAGS += -isystem $(shell $(CC) -print-file-name=include) -ifeq ($(ARCH),arm) -NEON_FLAGS += -march=armv7-a -mfloat-abi=softfp -mfpu=neon -endif -CFLAGS_recov_neon_inner.o += $(NEON_FLAGS) -ifeq ($(ARCH),arm64) -CFLAGS_REMOVE_recov_neon_inner.o += -mgeneral-regs-only -CFLAGS_REMOVE_neon1.o += -mgeneral-regs-only -CFLAGS_REMOVE_neon2.o += -mgeneral-regs-only -CFLAGS_REMOVE_neon4.o += -mgeneral-regs-only -CFLAGS_REMOVE_neon8.o += -mgeneral-regs-only -endif -endif - quiet_cmd_unroll = UNROLL $@ cmd_unroll = $(AWK) -v N=$* -f $(srctree)/$(src)/unroll.awk < $< > $@ @@ -75,10 +56,14 @@ targets += vpermxor1.c vpermxor2.c vpermxor4.c vpermxor8.c $(obj)/vpermxor%.c: $(src)/vpermxor.uc $(src)/unroll.awk FORCE $(call if_changed,unroll) -CFLAGS_neon1.o += $(NEON_FLAGS) -CFLAGS_neon2.o += $(NEON_FLAGS) -CFLAGS_neon4.o += $(NEON_FLAGS) -CFLAGS_neon8.o += $(NEON_FLAGS) +CFLAGS_neon1.o += $(CC_FLAGS_FPU) +CFLAGS_neon2.o += $(CC_FLAGS_FPU) +CFLAGS_neon4.o += $(CC_FLAGS_FPU) +CFLAGS_neon8.o += $(CC_FLAGS_FPU) +CFLAGS_REMOVE_neon1.o += $(CC_FLAGS_NO_FPU) +CFLAGS_REMOVE_neon2.o += $(CC_FLAGS_NO_FPU) +CFLAGS_REMOVE_neon4.o += $(CC_FLAGS_NO_FPU) +CFLAGS_REMOVE_neon8.o += $(CC_FLAGS_NO_FPU) targets += neon1.c neon2.c neon4.c neon8.c $(obj)/neon%.c: $(src)/neon.uc $(src)/unroll.awk FORCE $(call if_changed,unroll)
Now that CC_FLAGS_FPU is exported and can be used anywhere in the source tree, use it instead of duplicating the flags here. Signed-off-by: Samuel Holland <samuel.holland@sifive.com> --- lib/raid6/Makefile | 31 ++++++++----------------------- 1 file changed, 8 insertions(+), 23 deletions(-)