clang: Build limited targets for target clang recipe

On target its sufficient to build what mesa needs + one host target
It should speed up the build.

Fix bug in function mapping target architecture to LLVM backend

Reduces size of libLLVM

Before - 131M May  6 20:42 ./clang-libllvm/usr/lib/libLLVM.so.20.1
After  - 93M May  6 18:47 ./clang-libllvm/usr/lib/libLLVM.so.20.1

(From OE-Core rev: 0e1c55d2631200f8c9890eac8d26c404f28862d3)

Signed-off-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 9 insertions, 5 deletions

diff --git a/meta/recipes-devtools/clang/clang_git.bb b/meta/recipes-devtools/clang/clang_git.bb
index c93554622f..b41b700292 100644
--- a/meta/recipes-devtools/clang/clang_git.bb
+++ b/meta/recipes-devtools/clang/clang_git.bb
@@ -35,10 +35,10 @@ def get_clang_arch(bb, d, arch_var):
     elif re.match('aarch64$', a):                      return 'AArch64'
     elif re.match('aarch64_be$', a):                   return 'AArch64'
     elif re.match('mips(isa|)(32|64|)(r6|)(el|)$', a): return 'Mips'
-    elif re.match('riscv32$', a):                      return 'riscv32'
-    elif re.match('riscv64$', a):                      return 'riscv64'
+    elif re.match('riscv32$', a):                      return 'RISCV'
+    elif re.match('riscv64$', a):                      return 'RISCV'
     elif re.match('p(pc|owerpc)(|64)', a):             return 'PowerPC'
-    elif re.match('loongarch64$', a):                  return 'loongarch64'
+    elif re.match('loongarch64$', a):                  return 'LoongArch'
     else:
         bb.note("'%s' is not a primary llvm architecture" % a)
     return ""
@@ -115,8 +115,12 @@ LLVM_BUILD_TOOLS;LLVM_USE_HOST_TOOLS;LLVM_CONFIG_PATH;LLVM_EXTERNAL_SPIRV_HEADER
 # Default to build all OE-Core supported target arches (user overridable).
 # Gennerally setting LLVM_TARGETS_TO_BUILD = "" in local.conf is ok in most simple situations
 # where only one target architecture is needed along with just one build arch (usually X86)
-#
+# Core tier targets:
+# AArch64;AMDGPU;ARM;AVR;BPF;Hexagon;Lanai;LoongArch;Mips;MSP430;NVPTX;PowerPC;RISCV;Sparc;SPIRV;SystemZ;VE;WebAssembly;X86;XCore
+# Known experimental targets: ARC;CSKY;DirectX;M68k;Xtensa
+
 LLVM_TARGETS_TO_BUILD ?= "AMDGPU;AArch64;ARM;BPF;Mips;PowerPC;RISCV;X86;LoongArch;NVPTX;SPIRV"
+LLVM_TARGETS_TO_BUILD:class-target ?= "${@get_clang_host_arch(bb, d)};AMDGPU;BPF;NVPTX;SPIRV"
 
 LLVM_EXPERIMENTAL_TARGETS_TO_BUILD ?= ""
 
@@ -189,7 +193,7 @@ EXTRA_OECMAKE:append:class-target = "\
                   -DCMAKE_AR=${STAGING_BINDIR_TOOLCHAIN}/${TARGET_PREFIX}llvm-ar \
                   -DCMAKE_NM=${STAGING_BINDIR_TOOLCHAIN}/${TARGET_PREFIX}llvm-nm \
                   -DCMAKE_STRIP=${STAGING_BINDIR_TOOLCHAIN}/${TARGET_PREFIX}llvm-strip \
-                  -DLLVM_TARGET_ARCH=${@get_clang_target_arch(bb, d)} \
+                  -DLLVM_TARGET_ARCH=${HOST_ARCH} \
                   -DLLVM_DEFAULT_TARGET_TRIPLE=${TARGET_SYS}${HF} \
                   -DLLVM_HOST_TRIPLE=${TARGET_SYS}${HF} \
                   -DPYTHON_LIBRARY=${STAGING_LIBDIR}/lib${PYTHON_DIR}${PYTHON_ABI}.so \