[clang] [llvm] [RISCV][FMV] Support target_clones (PR #85786)

[Craig Topper via cfe-commits]

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@@ -0,0 +1,14 @@
+// RUN: not %clang_cc1 -triple riscv64-linux-gnu -target-feature +i -S -emit-llvm -o - %s 2>&1 | FileCheck %s --check-prefix=CHECK-UNSUPPORT-EXT
+// RUN: not %clang_cc1 -triple riscv64 -target-feature +i -S -emit-llvm -o - %s 2>&1 | FileCheck %s --check-prefix=CHECK-UNSUPPORT-OS
+
+// CHECK-UNSUPPORT-EXT: error: Unsupport 'zicsr' for _riscv_hwprobe
+__attribute__((target_clones("default", "arch=+zicsr"))) int foo1(void) {
+  return 1;
+}
+
+// CHECK-UNSUPPORT-OS: error: Only Linux support _riscv_hwprobe
----------------
topperc wrote:

`_riscv_hwprobe is only supported on Linux`

https://github.com/llvm/llvm-project/pull/85786