commit 12c0281f8c73bc1aa20d1517357e0e12c3f8bb4e
author Fangrui Song <i@maskray.me> Thu Jun 20 23:26:15 2024 -0700
committer Fangrui Song <i@maskray.me> Thu Jun 20 23:26:15 2024 -0700
tree 589178e2afcdbc58d7f13f0d417ff3bcbda2250f
parent 84728629c37c8463910860f9b5531ba18d03a9a8

[Lex] Replace hash_combine with a stable hash

clang/lib/Lex/HeaderSearch.cpp

diff --git a/clang/lib/Lex/HeaderSearch.cpp b/clang/lib/Lex/HeaderSearch.cpp
index 3bd3aa4..c3b3064 100644
--- a/clang/lib/Lex/HeaderSearch.cpp
+++ b/clang/lib/Lex/HeaderSearch.cpp
@@ -25,11 +25,11 @@
 #include "clang/Lex/Preprocessor.h"
 #include "llvm/ADT/APInt.h"
 #include "llvm/ADT/Hashing.h"
+#include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/ADT/StringRef.h"
-#include "llvm/ADT/STLExtras.h"
 #include "llvm/Support/Allocator.h"
 #include "llvm/Support/Capacity.h"
 #include "llvm/Support/Errc.h"
@@ -37,6 +37,7 @@
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Support/VirtualFileSystem.h"
+#include "llvm/Support/xxhash.h"
 #include <algorithm>
 #include <cassert>
 #include <cstddef>
@@ -282,10 +283,10 @@
     if (getModuleMap().canonicalizeModuleMapPath(CanonicalPath))
       return {};
 
-    llvm::hash_code Hash = llvm::hash_combine(CanonicalPath.str().lower());
+    auto Hash = llvm::xxh3_64bits(CanonicalPath.str().lower());
 
     SmallString<128> HashStr;
-    llvm::APInt(64, size_t(Hash)).toStringUnsigned(HashStr, /*Radix*/36);
+    llvm::APInt(64, Hash).toStringUnsigned(HashStr, /*Radix*/36);
     llvm::sys::path::append(Result, ModuleName + "-" + HashStr + ".pcm");
   }
   return Result.str().str();