1 files changed, 60 insertions, 0 deletions
diff --git a/lib/CodeGen/RuntimeCheck.cc b/lib/CodeGen/RuntimeCheck.cc
new file mode 100644
index 0000000..cab50d5
--- /dev/null
+++ b/lib/CodeGen/RuntimeCheck.cc
@@ -0,0 +1,60 @@
+#include "cps/RuntimeCheck.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/Type.h"
+#include "llvm/IR/Constants.h"
+
+using namespace llvm;
+using namespace cps;
+
+RuntimeCheck::RuntimeCheck(Module &M, LLVMContext &C, IRBuilder<> &B)
+    : TheModule(M), TheContext(C), Builder(B) {
+    setupExternalFunctions();
+}
+
+void RuntimeCheck::setupExternalFunctions() {
+    std::vector<Type*> PrintfArgs;
+    PrintfArgs.push_back(PointerType::getUnqual(TheContext));
+    FunctionType *PrintfType = FunctionType::get(Type::getInt32Ty(TheContext), PrintfArgs, true);
+    PrintfFunc = TheModule.getOrInsertFunction("printf", PrintfType);
+
+    std::vector<Type*> ExitArgs;
+    ExitArgs.push_back(Type::getInt32Ty(TheContext));
+    FunctionType *ExitType = FunctionType::get(Type::getVoidTy(TheContext), ExitArgs, false);
+    ExitFunc = TheModule.getOrInsertFunction("exit", ExitType);
+
+    DivZeroMsg = Builder.CreateGlobalStringPtr("[Fatal] line %d: Division by zero\n", "err_div_zero", 0, &TheModule);
+    OutOfBoundsMsg = Builder.CreateGlobalStringPtr("[Fatal] line %d: Array index out of bounds\n", "err_bounds", 0, &TheModule);
+}
+
+void RuntimeCheck::emitErrorAndExit(Value *Condition, Value *Msg, int Line) {
+    Function *TheFunction = Builder.GetInsertBlock()->getParent();
+    
+    BasicBlock *FailBB = BasicBlock::Create(TheContext, "check_fail", TheFunction);
+    BasicBlock *ContBB = BasicBlock::Create(TheContext, "check_cont", TheFunction);
+
+    Builder.CreateCondBr(Condition, FailBB, ContBB);
+
+    Builder.SetInsertPoint(FailBB);
+    std::vector<Value*> PrintArgs;
+    PrintArgs.push_back(Msg);
+    PrintArgs.push_back(ConstantInt::get(TheContext, APInt(32, Line)));
+    Builder.CreateCall(PrintfFunc, PrintArgs);
+
+    Builder.CreateCall(ExitFunc, ConstantInt::get(TheContext, APInt(32, 1)));
+    Builder.CreateUnreachable();
+
+    Builder.SetInsertPoint(ContBB);
+}
+
+void RuntimeCheck::emitDivZeroCheck(Value *Divisor, int Line) {
+    Value *IsZero = Builder.CreateICmpEQ(Divisor, ConstantInt::get(TheContext, APInt(32, 0)), "is_zero");
+    emitErrorAndExit(IsZero, DivZeroMsg, Line);
+}
+
+void RuntimeCheck::emitIndexCheck(Value *Index, Value *Lower, Value *Upper, int Line) {
+    Value *TooLow = Builder.CreateICmpSLT(Index, Lower, "too_low");
+    Value *TooHigh = Builder.CreateICmpSGT(Index, Upper, "too_high");
+    Value *OutOfBounds = Builder.CreateOr(TooLow, TooHigh, "out_of_bounds");
+    
+    emitErrorAndExit(OutOfBounds, OutOfBoundsMsg, Line);
+}