1 //===-------- BasicOrcV2CBindings.c - Basic OrcV2 C Bindings Demo ---------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8
9 #include "llvm-c/Core.h"
10 #include "llvm-c/Error.h"
11 #include "llvm-c/Initialization.h"
12 #include "llvm-c/LLJIT.h"
13 #include "llvm-c/Support.h"
14 #include "llvm-c/Target.h"
15
16 #include <stdio.h>
17
handleError(LLVMErrorRef Err)18 int handleError(LLVMErrorRef Err) {
19 char *ErrMsg = LLVMGetErrorMessage(Err);
20 fprintf(stderr, "Error: %s\n", ErrMsg);
21 LLVMDisposeErrorMessage(ErrMsg);
22 return 1;
23 }
24
createDemoModule()25 LLVMOrcThreadSafeModuleRef createDemoModule() {
26 // Create a new ThreadSafeContext and underlying LLVMContext.
27 LLVMOrcThreadSafeContextRef TSCtx = LLVMOrcCreateNewThreadSafeContext();
28
29 // Get a reference to the underlying LLVMContext.
30 LLVMContextRef Ctx = LLVMOrcThreadSafeContextGetContext(TSCtx);
31
32 // Create a new LLVM module.
33 LLVMModuleRef M = LLVMModuleCreateWithNameInContext("demo", Ctx);
34
35 // Add a "sum" function":
36 // - Create the function type and function instance.
37 LLVMTypeRef ParamTypes[] = {LLVMInt32Type(), LLVMInt32Type()};
38 LLVMTypeRef SumFunctionType =
39 LLVMFunctionType(LLVMInt32Type(), ParamTypes, 2, 0);
40 LLVMValueRef SumFunction = LLVMAddFunction(M, "sum", SumFunctionType);
41
42 // - Add a basic block to the function.
43 LLVMBasicBlockRef EntryBB = LLVMAppendBasicBlock(SumFunction, "entry");
44
45 // - Add an IR builder and point it at the end of the basic block.
46 LLVMBuilderRef Builder = LLVMCreateBuilder();
47 LLVMPositionBuilderAtEnd(Builder, EntryBB);
48
49 // - Get the two function arguments and use them co construct an "add"
50 // instruction.
51 LLVMValueRef SumArg0 = LLVMGetParam(SumFunction, 0);
52 LLVMValueRef SumArg1 = LLVMGetParam(SumFunction, 1);
53 LLVMValueRef Result = LLVMBuildAdd(Builder, SumArg0, SumArg1, "result");
54
55 // - Build the return instruction.
56 LLVMBuildRet(Builder, Result);
57
58 // Our demo module is now complete. Wrap it and our ThreadSafeContext in a
59 // ThreadSafeModule.
60 LLVMOrcThreadSafeModuleRef TSM = LLVMOrcCreateNewThreadSafeModule(M, TSCtx);
61
62 // Dispose of our local ThreadSafeContext value. The underlying LLVMContext
63 // will be kept alive by our ThreadSafeModule, TSM.
64 LLVMOrcDisposeThreadSafeContext(TSCtx);
65
66 // Return the result.
67 return TSM;
68 }
69
main(int argc,char * argv[])70 int main(int argc, char *argv[]) {
71
72 int MainResult = 0;
73
74 // Parse command line arguments and initialize LLVM Core.
75 LLVMParseCommandLineOptions(argc, (const char **)argv, "");
76 LLVMInitializeCore(LLVMGetGlobalPassRegistry());
77
78 // Initialize native target codegen and asm printer.
79 LLVMInitializeNativeTarget();
80 LLVMInitializeNativeAsmPrinter();
81
82 // Create the JIT instance.
83 LLVMOrcLLJITRef J;
84 {
85 LLVMErrorRef Err;
86 if ((Err = LLVMOrcCreateLLJIT(&J, 0))) {
87 MainResult = handleError(Err);
88 goto llvm_shutdown;
89 }
90 }
91
92 // Create our demo module.
93 LLVMOrcThreadSafeModuleRef TSM = createDemoModule();
94
95 // Add our demo module to the JIT.
96 {
97 LLVMOrcJITDylibRef MainJD = LLVMOrcLLJITGetMainJITDylib(J);
98 LLVMErrorRef Err;
99 if ((Err = LLVMOrcLLJITAddLLVMIRModule(J, MainJD, TSM))) {
100 // If adding the ThreadSafeModule fails then we need to clean it up
101 // ourselves. If adding it succeeds the JIT will manage the memory.
102 LLVMOrcDisposeThreadSafeModule(TSM);
103 MainResult = handleError(Err);
104 goto jit_cleanup;
105 }
106 }
107
108 // Look up the address of our demo entry point.
109 LLVMOrcJITTargetAddress SumAddr;
110 {
111 LLVMErrorRef Err;
112 if ((Err = LLVMOrcLLJITLookup(J, &SumAddr, "sum"))) {
113 MainResult = handleError(Err);
114 goto jit_cleanup;
115 }
116 }
117
118 // If we made it here then everything succeeded. Execute our JIT'd code.
119 int32_t (*Sum)(int32_t, int32_t) = (int32_t(*)(int32_t, int32_t))SumAddr;
120 int32_t Result = Sum(1, 2);
121
122 // Print the result.
123 printf("1 + 2 = %i\n", Result);
124
125 jit_cleanup:
126 // Destroy our JIT instance. This will clean up any memory that the JIT has
127 // taken ownership of. This operation is non-trivial (e.g. it may need to
128 // JIT static destructors) and may also fail. In that case we want to render
129 // the error to stderr, but not overwrite any existing return value.
130 {
131 LLVMErrorRef Err;
132 if ((Err = LLVMOrcDisposeLLJIT(J))) {
133 int NewFailureResult = handleError(Err);
134 if (MainResult == 0)
135 MainResult = NewFailureResult;
136 }
137 }
138
139 llvm_shutdown:
140 // Shut down LLVM.
141 LLVMShutdown();
142
143 return MainResult;
144 }
145