[compiler-rt] [tsan][riscv] add Go race detector support for RISC-V sv39 VMA (PR #154701)

[Thurston Dang via llvm-commits]

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@@ -681,6 +681,33 @@ struct MappingGoMips64_47 {
   static const uptr kShadowAdd = 0x200000000000ull;
 };
 
+/* Go on linux/riscv64 (39-bit VMA)
+0000 0000 0000 - 000a 0000 0000: executable and heap (40 GiB)
+000a 0000 0000 - 000c 0000 0000: -
+000c 0000 0000 - 0034 0000 0000: shadow - 160 GiB ( ~ 4 * app)
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thurstond wrote:

It doesn't really hurt (assuming the platform supports noreserve mappings), but this is unnecessarily large - it only needs to be 2x.

https://github.com/llvm/llvm-project/pull/154701