llvm/examples/OrcV2Examples/OrcV2CBindingsAddObjectFile/OrcV2CBindingsAddObjectFile.c

   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/LLJIT.h"
  12 #include "llvm-c/Support.h"
  13 #include "llvm-c/Target.h"
  14 #include "llvm-c/TargetMachine.h"
  15
  16 #include <stdio.h>
  17
  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
  25 LLVMModuleRef createDemoModule(LLVMContextRef Ctx) {
  26   // Create a new LLVM module.
  27   LLVMModuleRef M = LLVMModuleCreateWithNameInContext("demo", Ctx);
  28
  29   // Add a "sum" function":
  30   //  - Create the function type and function instance.
  31   LLVMTypeRef ParamTypes[] = {LLVMInt32Type(), LLVMInt32Type()};
  32   LLVMTypeRef SumFunctionType =
  33       LLVMFunctionType(LLVMInt32Type(), ParamTypes, 2, 0);
  34   LLVMValueRef SumFunction = LLVMAddFunction(M, "sum", SumFunctionType);
  35
  36   //  - Add a basic block to the function.
  37   LLVMBasicBlockRef EntryBB = LLVMAppendBasicBlock(SumFunction, "entry");
  38
  39   //  - Add an IR builder and point it at the end of the basic block.
  40   LLVMBuilderRef Builder = LLVMCreateBuilder();
  41   LLVMPositionBuilderAtEnd(Builder, EntryBB);
  42
  43   //  - Get the two function arguments and use them co construct an "add"
  44   //    instruction.
  45   LLVMValueRef SumArg0 = LLVMGetParam(SumFunction, 0);
  46   LLVMValueRef SumArg1 = LLVMGetParam(SumFunction, 1);
  47   LLVMValueRef Result = LLVMBuildAdd(Builder, SumArg0, SumArg1, "result");
  48
  49   //  - Build the return instruction.
  50   LLVMBuildRet(Builder, Result);
  51
  52   //  - Free the builder.
  53   LLVMDisposeBuilder(Builder);
  54
  55   return M;
  56 }
  57
  58 int main(int argc, const char *argv[]) {
  59
  60   int MainResult = 0;
  61
  62   // Parse command line arguments and initialize LLVM Core.
  63   LLVMParseCommandLineOptions(argc, argv, "");
  64
  65   // Initialize native target codegen and asm printer.
  66   LLVMInitializeNativeTarget();
  67   LLVMInitializeNativeAsmPrinter();
  68
  69   // Create the JIT instance.
  70   LLVMOrcLLJITRef J;
  71   {
  72     LLVMErrorRef Err;
  73     if ((Err = LLVMOrcCreateLLJIT(&J, 0))) {
  74       MainResult = handleError(Err);
  75       goto llvm_shutdown;
  76     }
  77   }
  78
  79   // Create our demo object file.
  80   LLVMMemoryBufferRef ObjectFileBuffer;
  81   {
  82     // Create a module.
  83     LLVMContextRef Ctx = LLVMContextCreate();
  84     LLVMModuleRef M = createDemoModule(Ctx);
  85
  86     // Get the Target.
  87     const char *Triple = LLVMOrcLLJITGetTripleString(J);
  88     LLVMTargetRef Target = 0;
  89     char *ErrorMsg = 0;
  90     if (LLVMGetTargetFromTriple(Triple, &Target, &ErrorMsg)) {
  91       fprintf(stderr, "Error getting target for %s: %s\n", Triple, ErrorMsg);
  92       LLVMDisposeModule(M);
  93       LLVMContextDispose(Ctx);
  94       goto jit_cleanup;
  95     }
  96
  97     // Construct a TargetMachine.
  98     LLVMTargetMachineRef TM =
  99         LLVMCreateTargetMachine(Target, Triple, "", "", LLVMCodeGenLevelNone,
 100                                 LLVMRelocDefault, LLVMCodeModelDefault);
 101
 102     // Run CodeGen to produce the buffer.
 103     if (LLVMTargetMachineEmitToMemoryBuffer(TM, M, LLVMObjectFile, &ErrorMsg,
 104                                             &ObjectFileBuffer)) {
 105       fprintf(stderr, "Error emitting object: %s\n", ErrorMsg);
 106       LLVMDisposeTargetMachine(TM);
 107       LLVMDisposeModule(M);
 108       LLVMContextDispose(Ctx);
 109       goto jit_cleanup;
 110     }
 111
 112     // CodeGen succeeded -- We have our module, so free the Module, LLVMContext,
 113     // and TargetMachine.
 114     LLVMDisposeModule(M);
 115     LLVMContextDispose(Ctx);
 116     LLVMDisposeTargetMachine(TM);
 117   }
 118
 119   // Add our object file buffer to the JIT.
 120   {
 121     LLVMOrcJITDylibRef MainJD = LLVMOrcLLJITGetMainJITDylib(J);
 122     LLVMErrorRef Err;
 123     if ((Err = LLVMOrcLLJITAddObjectFile(J, MainJD, ObjectFileBuffer))) {
 124       MainResult = handleError(Err);
 125       goto jit_cleanup;
 126     }
 127   }
 128
 129   // Look up the address of our demo entry point.
 130   LLVMOrcJITTargetAddress SumAddr;
 131   {
 132     LLVMErrorRef Err;
 133     if ((Err = LLVMOrcLLJITLookup(J, &SumAddr, "sum"))) {
 134       MainResult = handleError(Err);
 135       goto jit_cleanup;
 136     }
 137   }
 138
 139   // If we made it here then everything succeeded. Execute our JIT'd code.
 140   int32_t (*Sum)(int32_t, int32_t) = (int32_t(*)(int32_t, int32_t))SumAddr;
 141   int32_t Result = Sum(1, 2);
 142
 143   // Print the result.
 144   printf("1 + 2 = %i\n", Result);
 145
 146 jit_cleanup:
 147   // Destroy our JIT instance. This will clean up any memory that the JIT has
 148   // taken ownership of. This operation is non-trivial (e.g. it may need to
 149   // JIT static destructors) and may also fail. In that case we want to render
 150   // the error to stderr, but not overwrite any existing return value.
 151   {
 152     LLVMErrorRef Err;
 153     if ((Err = LLVMOrcDisposeLLJIT(J))) {
 154       int NewFailureResult = handleError(Err);
 155       if (MainResult == 0)
 156         MainResult = NewFailureResult;
 157     }
 158   }
 159
 160 llvm_shutdown:
 161   // Shut down LLVM.
 162   LLVMShutdown();
 163
 164   return MainResult;
 165 }