[compiler-rt] [compiler-rt][lsan][Fuchsia] Adjust lsan allocator settings (PR #69401)

[via llvm-commits]

https://github.com/PiJoules created https://github.com/llvm/llvm-project/pull/69401

These now match the settings for the asan allocator on Fuchsia+RISCV.

>From 84a1ee55bf1c2e5844c8042fb24bcc2128a54051 Mon Sep 17 00:00:00 2001
From: Leonard Chan <leonardchan at google.com>
Date: Wed, 18 Oct 2023 00:19:10 +0000
Subject: [PATCH] [compiler-rt][lsan][Fuchsia] Adjust lsan allocator settings

These now match the settings for the asan allocator on Fuchsia+RISCV.
---
 compiler-rt/lib/lsan/lsan_allocator.h | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/compiler-rt/lib/lsan/lsan_allocator.h b/compiler-rt/lib/lsan/lsan_allocator.h
index f5486150a8121f1..7761e7f1e2ebd14 100644
--- a/compiler-rt/lib/lsan/lsan_allocator.h
+++ b/compiler-rt/lib/lsan/lsan_allocator.h
@@ -68,23 +68,43 @@ using PrimaryAllocator = PrimaryAllocatorASVT<LocalAddressSpaceView>;
 #else
 # if SANITIZER_FUCHSIA || defined(__powerpc64__)
 const uptr kAllocatorSpace = ~(uptr)0;
+#    if SANITIZER_RISCV64
+// See the comments in compiler-rt/lib/asan/asan_allocator.h for why these
+// values were chosen.
+const uptr kAllocatorSize = UINT64_C(1) << 33;  // 8GB
+typedef SizeClassMap</*kNumBits=*/2,
+                     /*kMinSizeLog=*/5,
+                     /*kMidSizeLog=*/8,
+                     /*kMaxSizeLog=*/18,
+                     /*kNumCachedHintT=*/8,
+                     /*kMaxBytesCachedLog=*/10>
+    SizeClassMap;
+static_assert(SizeClassMap::kNumClassesRounded <= 32,
+              "32 size classes is the optimal number to ensure tests run "
+              "effieciently on Fuchsia.");
+#    else
 const uptr kAllocatorSize  =  0x40000000000ULL;  // 4T.
+typedef DefaultSizeClassMap SizeClassMap;
+#    endif
 #  elif SANITIZER_RISCV64
 const uptr kAllocatorSpace = ~(uptr)0;
 const uptr kAllocatorSize = 0x2000000000ULL;  // 128G.
+typedef DefaultSizeClassMap SizeClassMap;
 #  elif SANITIZER_APPLE
 const uptr kAllocatorSpace = 0x600000000000ULL;
 const uptr kAllocatorSize  = 0x40000000000ULL;  // 4T.
+typedef DefaultSizeClassMap SizeClassMap;
 #  else
 const uptr kAllocatorSpace = 0x500000000000ULL;
 const uptr kAllocatorSize = 0x40000000000ULL;  // 4T.
+typedef DefaultSizeClassMap SizeClassMap;
 #  endif
 template <typename AddressSpaceViewTy>
 struct AP64 {  // Allocator64 parameters. Deliberately using a short name.
   static const uptr kSpaceBeg = kAllocatorSpace;
   static const uptr kSpaceSize = kAllocatorSize;
   static const uptr kMetadataSize = sizeof(ChunkMetadata);
-  typedef DefaultSizeClassMap SizeClassMap;
+  typedef SizeClassMap SizeClassMap;
   typedef NoOpMapUnmapCallback MapUnmapCallback;
   static const uptr kFlags = 0;
   using AddressSpaceView = AddressSpaceViewTy;