kbuild: add test-{ge,gt,le,lt} macros

GNU Make 4.4 introduced $(intcmp ...), which is useful to compare two
integers without forking a new process.

Add test-{ge,gt,le,lt} macros, which work more efficiently with GNU
Make >= 4.4. For older Make versions, they fall back to the 'test'
shell command.

The first two parameters to $(intcmp ...) must not be empty. To avoid
the syntax error, I appended '0' to them. Fortunately, '00' is treated
as '0'. This is needed because CONFIG options may expand to an empty
string when the kernel configuration is not included.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com> # RISC-V
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
This commit is contained in:
Masahiro Yamada 2022-12-11 11:46:47 +09:00
parent e441273947
commit fccb3d3eda
5 changed files with 21 additions and 5 deletions

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@ -994,7 +994,7 @@ KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
# Check for frame size exceeding threshold during prolog/epilog insertion
# when using lld < 13.0.0.
ifneq ($(CONFIG_FRAME_WARN),0)
ifeq ($(shell test $(CONFIG_LLD_VERSION) -lt 130000; echo $$?),0)
ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 130000),y)
KBUILD_LDFLAGS += -plugin-opt=-warn-stack-size=$(CONFIG_FRAME_WARN)
endif
endif

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@ -37,7 +37,7 @@ else
endif
ifeq ($(CONFIG_LD_IS_LLD),y)
ifeq ($(shell test $(CONFIG_LLD_VERSION) -lt 150000; echo $$?),0)
ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 150000),y)
KBUILD_CFLAGS += -mno-relax
KBUILD_AFLAGS += -mno-relax
ifndef CONFIG_AS_IS_LLVM

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@ -211,7 +211,7 @@ endif
KBUILD_LDFLAGS += -m elf_$(UTS_MACHINE)
ifdef CONFIG_LTO_CLANG
ifeq ($(shell test $(CONFIG_LLD_VERSION) -lt 130000; echo $$?),0)
ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 130000),y)
KBUILD_LDFLAGS += -plugin-opt=-stack-alignment=$(if $(CONFIG_X86_32),4,8)
endif
endif

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@ -11,6 +11,22 @@ space := $(empty) $(empty)
space_escape := _-_SPACE_-_
pound := \#
###
# Comparison macros.
# Usage: $(call test-lt, $(CONFIG_LLD_VERSION), 150000)
#
# Use $(intcmp ...) if supported. (Make >= 4.4)
# Otherwise, fall back to the 'test' shell command.
ifeq ($(intcmp 1,0,,,y),y)
test-ge = $(intcmp $(strip $1)0, $(strip $2)0,,y,y)
test-gt = $(intcmp $(strip $1)0, $(strip $2)0,,,y)
else
test-ge = $(shell test $(strip $1)0 -ge $(strip $2)0 && echo y)
test-gt = $(shell test $(strip $1)0 -gt $(strip $2)0 && echo y)
endif
test-le = $(call test-ge, $2, $1)
test-lt = $(call test-gt, $2, $1)
###
# Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o
dot-target = $(dir $@).$(notdir $@)

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@ -63,11 +63,11 @@ cc-disable-warning = $(call try-run,\
# gcc-min-version
# Usage: cflags-$(call gcc-min-version, 70100) += -foo
gcc-min-version = $(shell [ $(CONFIG_GCC_VERSION)0 -ge $(1)0 ] && echo y)
gcc-min-version = $(call test-ge, $(CONFIG_GCC_VERSION), $1)
# clang-min-version
# Usage: cflags-$(call clang-min-version, 110000) += -foo
clang-min-version = $(shell [ $(CONFIG_CLANG_VERSION)0 -ge $(1)0 ] && echo y)
clang-min-version = $(call test-ge, $(CONFIG_CLANG_VERSION), $1)
# ld-option
# Usage: KBUILD_LDFLAGS += $(call ld-option, -X, -Y)