xref: /aosp_15_r20/external/angle/src/compiler/translator/HashNames.cpp (revision 8975f5c5ed3d1c378011245431ada316dfb6f244)
1 //
2 // Copyright 2017 The ANGLE Project Authors. All rights reserved.
3 // Use of this source code is governed by a BSD-style license that can be
4 // found in the LICENSE file.
5 //
6 
7 #include "compiler/translator/HashNames.h"
8 
9 #include "compiler/translator/ImmutableString.h"
10 #include "compiler/translator/ImmutableStringBuilder.h"
11 #include "compiler/translator/IntermNode.h"
12 #include "compiler/translator/Symbol.h"
13 
14 namespace sh
15 {
16 
17 namespace
18 {
19 constexpr const ImmutableString kHashedNamePrefix("webgl_");
20 
HashName(const ImmutableString & name,ShHashFunction64 hashFunction)21 ImmutableString HashName(const ImmutableString &name, ShHashFunction64 hashFunction)
22 {
23     ASSERT(!name.empty());
24     ASSERT(hashFunction);
25     khronos_uint64_t number = (*hashFunction)(name.data(), name.length());
26 
27     // Build the hashed name in place.
28     static const unsigned int kHexStrMaxLength = sizeof(number) * 2;
29     static const size_t kHashedNameMaxLength   = kHashedNamePrefix.length() + kHexStrMaxLength;
30 
31     ImmutableStringBuilder hashedName(kHashedNameMaxLength);
32     hashedName << kHashedNamePrefix;
33 
34     hashedName.appendHex(number);
35 
36     return hashedName;
37 }
38 
AddToNameMapIfNotMapped(const ImmutableString & name,const ImmutableString & hashedName,NameMap * nameMap)39 void AddToNameMapIfNotMapped(const ImmutableString &name,
40                              const ImmutableString &hashedName,
41                              NameMap *nameMap)
42 {
43     if (nameMap)
44     {
45         NameMap::const_iterator it = nameMap->find(name.data());
46         if (it != nameMap->end())
47         {
48             // (How bout returning?)
49             return;
50         }
51         (*nameMap)[name.data()] = hashedName.data();
52     }
53 }
54 
55 }  // anonymous namespace
56 
HashName(const ImmutableString & name,ShHashFunction64 hashFunction,NameMap * nameMap)57 ImmutableString HashName(const ImmutableString &name,
58                          ShHashFunction64 hashFunction,
59                          NameMap *nameMap)
60 {
61     const ImmutableString kUnhashedNamePrefix(kUserDefinedNamePrefix);
62 
63     if (hashFunction == nullptr)
64     {
65         if (name.length() + kUnhashedNamePrefix.length() > kESSLMaxIdentifierLength)
66         {
67             // If the identifier length is already close to the limit, we can't prefix it. This is
68             // not a problem since there are no builtins or ANGLE's internal variables that would
69             // have as long names and could conflict.
70             return name;
71         }
72         ImmutableStringBuilder prefixedName(kUnhashedNamePrefix.length() + name.length());
73         prefixedName << kUnhashedNamePrefix << name;
74         ImmutableString res = prefixedName;
75         AddToNameMapIfNotMapped(name, res, nameMap);
76         return res;
77     }
78 
79     // Has a hash function
80     ImmutableString hashedName = HashName(name, hashFunction);
81     AddToNameMapIfNotMapped(name, hashedName, nameMap);
82     return hashedName;
83 }
84 
HashName(const TSymbol * symbol,ShHashFunction64 hashFunction,NameMap * nameMap)85 ImmutableString HashName(const TSymbol *symbol, ShHashFunction64 hashFunction, NameMap *nameMap)
86 {
87     if (symbol->symbolType() == SymbolType::Empty)
88     {
89         return kEmptyImmutableString;
90     }
91     if (symbol->symbolType() == SymbolType::AngleInternal ||
92         symbol->symbolType() == SymbolType::BuiltIn)
93     {
94         return symbol->name();
95     }
96     return HashName(symbol->name(), hashFunction, nameMap);
97 }
98 
99 }  // namespace sh
100