1 /*
2  * Copyright 2010-2012, The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *     http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include "bcc/Script.h"
18 
19 #include "Assert.h"
20 #include "Log.h"
21 
22 #include "bcc/CompilerConfig.h"
23 #include "bcc/Source.h"
24 
25 #include "bcinfo/MetadataExtractor.h"
26 
27 #include <llvm/IR/Module.h>
28 
29 using namespace bcc;
30 
Script(Source * pSource)31 Script::Script(Source *pSource)
32     : mSource(pSource),
33       mOptimizationLevel(llvm::CodeGenOpt::Aggressive),
34       mLinkRuntimeCallback(nullptr), mEmbedInfo(false), mEmbedGlobalInfo(false),
35       mEmbedGlobalInfoSkipConstant(false) {}
36 
LinkRuntime(const char * core_lib)37 bool Script::LinkRuntime(const char *core_lib) {
38   bccAssert(core_lib != nullptr);
39 
40   // Using the same context with the source.
41   BCCContext &context = mSource->getContext();
42 
43   Source *libclcore_source = Source::CreateFromFile(context, core_lib);
44   if (libclcore_source == nullptr) {
45     ALOGE("Failed to load Renderscript library '%s' to link!", core_lib);
46     return false;
47   }
48 
49   if (mLinkRuntimeCallback != nullptr) {
50     mLinkRuntimeCallback(this, &mSource->getModule(),
51                          &libclcore_source->getModule());
52   }
53 
54   // For every named metadata node in the source (libclcore_source),
55   // the merge process ensures there is a same-named metadata node in
56   // the destination (mSource) (creating it if necessary) and appends
57   // all of the source node's operands to the end of the destination
58   // node's operands.  In the case of the wrapper metadata
59   //
60   //   kWrapperMetadataName -> (compilerVersion, optimizationLevel)
61   //
62   // this is not the behavior we want.  Instead, we want to retain the
63   // source wrapper metadata:
64   // - compiler version in libclcore_source is 0, a nonsensical value.
65   //   As documented in slang_version.h, libclcore_source must not
66   //   violate any compiler version guarantees, so the right thing to
67   //   do is retain the compiler version from source, which specifies
68   //   which guarantees source (and hence the merged code) satisfies.
69   //   See frameworks/rs/driver/README.txt regarding libclcore_source
70   //   obeying compiler version guarantees.
71   // - optimization level in source and libclcore_source is meaningful.
72   //   We simply define the optimization level in the linked code to
73   //   be the optimization level of source.
74   // The easiest way to retain the source wrapper metadata is to delete
75   // the libclcore_source wrapper metadata.
76   llvm::Module &libclcore_module = libclcore_source->getModule();
77   llvm::NamedMDNode *const wrapperMDNode =
78       libclcore_module.getNamedMetadata(bcinfo::MetadataExtractor::kWrapperMetadataName);
79   bccAssert(wrapperMDNode != nullptr);
80   libclcore_module.eraseNamedMetadata(wrapperMDNode);
81   if (!mSource->merge(*libclcore_source)) {
82     ALOGE("Failed to link Renderscript library '%s'!", core_lib);
83     delete libclcore_source;
84     return false;
85   }
86 
87   return true;
88 }
89 
mergeSource(Source & pSource)90 bool Script::mergeSource(Source &pSource) { return mSource->merge(pSource); }
91