[clang] [RISCV] Support predefined marcro __riscv_misaligned_{fast,avoid}. (PR #65756)

[Fangrui Song via cfe-commits]

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@@ -1228,3 +1228,15 @@
 // RUN: -march=rv64i_zve32x_zvkt1p0 -x c -E -dM %s \
 // RUN: -o - | FileCheck --check-prefix=CHECK-ZVKT-EXT %s
 // CHECK-ZVKT-EXT: __riscv_zvkt 1000000{{$}}
+
+// RUN: %clang --target=riscv32-unknown-linux-gnu -march=rv32i -x c -E -dM %s \
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MaskRay wrote:

Remove `-x c` (redundant) and indent the continuation lines by 2

https://github.com/llvm/llvm-project/pull/65756