Add 32-bit hash helper to ImmutableString

Since the length of the hash is known prior to compilation, it can be compared with script-generated hashes. BUG=angleproject:2267 TEST=angle_unittests Change-Id: Ia0a78dfd450c4ea2d526da7f3495b9750dcbd1af Reviewed-on: https://chromium-review.googlesource.com/931884Reviewed-by: Corentin Wallez <cwallez@chromium.org> Reviewed-by: Jamie Madill <jmadill@chromium.org> Commit-Queue: Olli Etuaho <oetuaho@nvidia.com>

Add 32-bit hash helper to ImmutableString
c4bd0ac9 · Olli Etuaho · Commit Bot · 2f7c04a3 · c4bd0ac9 · c4bd0ac9
Commit c4bd0ac9 authored Feb 22, 2018 by Olli Etuaho Committed by Commit Bot Feb 26, 2018
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ImmutableString.cpp src/compiler/translator/ImmutableString.cpp +13 -0

ImmutableString.h src/compiler/translator/ImmutableString.h +2 -0

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--- a/src/compiler/translator/ImmutableString.cpp
+++ b/src/compiler/translator/ImmutableString.cpp
@@ -35,4 +35,17 @@ template <>
 const size_t ImmutableString::FowlerNollVoHash<8>::kFnvOffsetBasis =
    static_cast<size_t>(0xcbf29ce484222325ull);

+uint32_t ImmutableString::hash32() const
+{
+    const char *data_ptr = data();
+    uint32_t hash        = static_cast<uint32_t>(FowlerNollVoHash<4>::kFnvOffsetBasis);
+    while ((*data_ptr) != '\0')
+    {
+        hash = hash ^ (*data_ptr);
+        hash = hash * static_cast<uint32_t>(FowlerNollVoHash<4>::kFnvPrime);
+        ++data_ptr;
+    }
+    return hash;
+}
+
 }  // namespace sh
--- a/src/compiler/translator/ImmutableString.h
+++ b/src/compiler/translator/ImmutableString.h
@@ -128,6 +128,8 @@ class ImmutableString
        }
    };

+    uint32_t hash32() const;
+
  private:
    const char *mData;
    size_t mLength;