File CACHY-Add-x86_64-ISA-and-Zen4-compiler-optimizations.patch of Package linux-clear-llvm

diff '--color=auto' -ruN a/arch/x86/Kconfig.cpu b/arch/x86/Kconfig.cpu
--- a/arch/x86/Kconfig.cpu	2025-05-26 01:09:23.000000000 +0200
+++ b/arch/x86/Kconfig.cpu	2025-06-07 13:27:37.776184081 +0200
@@ -245,6 +245,76 @@
 
 endchoice
 
+config CC_HAS_MARCH_NATIVE
+	# This flag might not be available in cross-compilers:
+	def_bool $(cc-option, -march=native)
+	# LLVM 18 has an easily triggered internal compiler error in core
+	# networking code with '-march=native' on certain systems:
+	# https://github.com/llvm/llvm-project/issues/72026
+	# LLVM 19 introduces an optimization that resolves some high stack
+	# usage warnings that only appear wth '-march=native'.
+	depends on CC_IS_GCC || CLANG_VERSION >= 190100
+
+
+choice
+	prompt "x86_64 Compiler Build Optimization"
+	default GENERIC_CPU
+
+config X86_NATIVE_CPU
+	bool "Build and optimize for local/native CPU"
+	depends on X86_64
+	depends on CC_HAS_MARCH_NATIVE
+	help
+	  Optimize for the current CPU used to compile the kernel.
+	  Use this option if you intend to build the kernel for your
+	  local machine.
+
+	  Note that such a kernel might not work optimally on a
+	  different x86 machine.
+
+	  If unsure, say N.
+
+config GENERIC_CPU
+	bool "Generic-x86-64"
+	depends on X86_64
+	help
+	  Generic x86-64 CPU.
+          Runs equally well on all x86-64 CPUs.
+
+config MZEN4
+	bool "AMD Ryzen 4"
+	depends on (CC_IS_GCC && GCC_VERSION >= 130000) || (CC_IS_CLANG && CLANG_VERSION >= 160000)
+	help
+	  Select this for AMD Family 19h Zen 4 processors.
+
+          Enables -march=znver4
+
+endchoice
+
+config X86_64_VERSION
+	int "x86-64 compiler ISA level"
+	range 1 4
+	depends on (CC_IS_GCC && GCC_VERSION > 110000) || (CC_IS_CLANG && CLANG_VERSION >= 120000)
+	depends on X86_64 && GENERIC_CPU
+	help
+	  Specify a specific x86-64 compiler ISA level.
+
+	  There are three x86-64 ISA levels that work on top of
+	  the x86-64 baseline, namely: x86-64-v2 and x86-64-v3.
+
+	  x86-64-v2 brings support for vector instructions up to Streaming SIMD
+	  Extensions 4.2 (SSE4.2) and Supplemental Streaming SIMD Extensions 3
+	  (SSSE3), the POPCNT instruction, and CMPXCHG16B.
+
+	  x86-64-v3 adds vector instructions up to AVX2, MOVBE, and additional
+	  bit-manipulation instructions.
+
+	  x86-64-v4 is not included since the kernel does not use AVX512 instructions
+
+	  You can find the best version for your CPU by running one of the following:
+	  /lib/ld-linux-x86-64.so.2 --help | grep supported
+	  /lib64/ld-linux-x86-64.so.2 --help | grep supported
+
 config X86_GENERIC
 	bool "Generic x86 support"
 	depends on X86_32
diff '--color=auto' -ruN a/arch/x86/Makefile b/arch/x86/Makefile
--- a/arch/x86/Makefile	2025-05-26 01:09:23.000000000 +0200
+++ b/arch/x86/Makefile	2025-06-07 13:27:49.610275535 +0200
@@ -173,8 +173,25 @@
 	# Use -mskip-rax-setup if supported.
 	KBUILD_CFLAGS += $(call cc-option,-mskip-rax-setup)
 
+ifdef CONFIG_X86_NATIVE_CPU
+        KBUILD_CFLAGS += -march=native
+        KBUILD_RUSTFLAGS += -Ctarget-cpu=native
+endif
+
+ifdef CONFIG_MZEN4
+        KBUILD_CFLAGS += -march=znver4
+        KBUILD_RUSTFLAGS += -Ctarget-cpu=znver4
+endif
+
+ifdef CONFIG_GENERIC_CPU
+ifeq ($(CONFIG_X86_64_VERSION),1)
         KBUILD_CFLAGS += -march=x86-64 -mtune=generic
         KBUILD_RUSTFLAGS += -Ctarget-cpu=x86-64 -Ztune-cpu=generic
+else
+        KBUILD_CFLAGS +=-march=x86-64-v$(CONFIG_X86_64_VERSION)
+        KBUILD_RUSTFLAGS += -Ctarget-cpu=x86-64-v$(CONFIG_X86_64_VERSION)
+endif # CONFIG_X86_64_VERSION
+endif # CONFIG_GENERIC_CPU
 
         KBUILD_CFLAGS += -mno-red-zone
         KBUILD_CFLAGS += -mcmodel=kernel