[libc-commits] [PATCH] D145584: [libc] Add support for setjmp and longjmp in riscv

[Siva Chandra via Phabricator via libc-commits]

sivachandra added a comment.

I have left comments in `longjmp.cpp` but same questions apply for `setjmp.cpp` as well.



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Comment at: libc/src/setjmp/longjmp.cpp:18
+#if defined(LIBC_TARGET_ARCH_IS_RISCV64)
+__attribute__((naked)) // Don't generate function epilogue and prologue
+#endif
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Why is this required?


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Comment at: libc/src/setjmp/longjmp.cpp:64
+#pragma GCC diagnostic ignored "-Wuninitialized"
+  LIBC_INLINE_ASM("ld %0, 0(%1)\n\t" : "=r"(ra) : "r"(a0) :);
+  LIBC_INLINE_ASM("ld %0, 8(%1)\n\t" : "=r"(s0) : "r"(a0) :);
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Can't we directly reference `buf` instead of using these fixed offsets, much like how we do for x86_64 case?


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Comment at: libc/src/setjmp/longjmp.cpp:109
+
+  LIBC_INLINE_ASM("seqz %0, %1" : "=r"(a0) : "r"(a1) :);
+  LIBC_INLINE_ASM("add %0, %0, %1" : "=r"(a0) : "r"(a1), "r"(a0) :);
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Same here, can we read `val` instead of reading `a1`?


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D145584/new/

https://reviews.llvm.org/D145584