[compiler-rt] [llvm] [compiler-rt][msan] Add MSan support for RISC-V 64-bit Linux (PR #206674)

[Thurston Dang via llvm-commits]

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@@ -520,6 +520,14 @@ static const MemoryMapParams Linux_Hexagon_MemoryMapParams = {
 // FIXME: Remove -msan-origin-base -msan-and-mask added by PR #109284 to tests
 // after picking good constants
 
+// riscv64 Linux — SV39 (256GB)
+static const MemoryMapParams Linux_RISCV64_MemoryMapParams = {
+    0x3C00000000, // AndMask (fold bits 34-37)
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thurstond wrote:

Aliasing the shadow memory regions (and origin memory regions) can lead to strange false positives, false negatives, and incorrect origin tracking.

https://github.com/llvm/llvm-project/pull/206674