func (v *Codegen) genBoundsCheck(limit llvm.Value, index llvm.Value, indexType parser.Type) {
segvBlock := llvm.AddBasicBlock(v.currentLLVMFunction(), "boundscheck_segv")
endBlock := llvm.AddBasicBlock(v.currentLLVMFunction(), "boundscheck_end")
upperCheckBlock := llvm.AddBasicBlock(v.currentLLVMFunction(), "boundscheck_upper_block")
tooLow := v.builder().CreateICmp(llvm.IntSGT, llvm.ConstInt(index.Type(), 0, false), index, "boundscheck_lower")
v.builder().CreateCondBr(tooLow, segvBlock, upperCheckBlock)
v.builder().SetInsertPointAtEnd(upperCheckBlock)
// make sure limit and index have same width
castedLimit := limit
castedIndex := index
if index.Type().IntTypeWidth() < limit.Type().IntTypeWidth() {
if indexType.IsSigned() {
castedIndex = v.builder().CreateSExt(index, limit.Type(), "")
} else {
castedIndex = v.builder().CreateZExt(index, limit.Type(), "")
}
} else if index.Type().IntTypeWidth() > limit.Type().IntTypeWidth() {
castedLimit = v.builder().CreateZExt(limit, index.Type(), "")
}
tooHigh := v.builder().CreateICmp(llvm.IntSLE, castedLimit, castedIndex, "boundscheck_upper")
v.builder().CreateCondBr(tooHigh, segvBlock, endBlock)
v.builder().SetInsertPointAtEnd(segvBlock)
v.genRaiseSegfault()
v.builder().CreateUnreachable()
v.builder().SetInsertPointAtEnd(endBlock)
}
func (v *Codegen) genBinop(operator parser.BinOpType, resType, lhandType, rhandType parser.Type, lhand, rhand llvm.Value) llvm.Value {
if lhand.IsNil() || rhand.IsNil() {
v.err("invalid binary expr")
} else {
switch operator {
// Arithmetic
case parser.BINOP_ADD:
if resType.IsFloatingType() {
return v.builder().CreateFAdd(lhand, rhand, "")
} else {
return v.builder().CreateAdd(lhand, rhand, "")
}
case parser.BINOP_SUB:
if resType.IsFloatingType() {
return v.builder().CreateFSub(lhand, rhand, "")
} else {
return v.builder().CreateSub(lhand, rhand, "")
}
case parser.BINOP_MUL:
if resType.IsFloatingType() {
return v.builder().CreateFMul(lhand, rhand, "")
} else {
return v.builder().CreateMul(lhand, rhand, "")
}
case parser.BINOP_DIV:
if resType.IsFloatingType() {
return v.builder().CreateFDiv(lhand, rhand, "")
} else {
if resType.(parser.PrimitiveType).IsSigned() {
return v.builder().CreateSDiv(lhand, rhand, "")
} else {
return v.builder().CreateUDiv(lhand, rhand, "")
}
}
case parser.BINOP_MOD:
if resType.IsFloatingType() {
return v.builder().CreateFRem(lhand, rhand, "")
} else {
if resType.(parser.PrimitiveType).IsSigned() {
return v.builder().CreateSRem(lhand, rhand, "")
} else {
return v.builder().CreateURem(lhand, rhand, "")
}
}
// Comparison
case parser.BINOP_GREATER, parser.BINOP_LESS, parser.BINOP_GREATER_EQ, parser.BINOP_LESS_EQ, parser.BINOP_EQ, parser.BINOP_NOT_EQ:
if lhandType.IsFloatingType() {
return v.builder().CreateFCmp(comparisonOpToFloatPredicate(operator), lhand, rhand, "")
} else {
return v.builder().CreateICmp(comparisonOpToIntPredicate(operator, lhandType.IsSigned()), lhand, rhand, "")
}
// Bitwise
case parser.BINOP_BIT_AND:
return v.builder().CreateAnd(lhand, rhand, "")
case parser.BINOP_BIT_OR:
return v.builder().CreateOr(lhand, rhand, "")
case parser.BINOP_BIT_XOR:
return v.builder().CreateXor(lhand, rhand, "")
case parser.BINOP_BIT_LEFT:
return v.builder().CreateShl(lhand, rhand, "")
case parser.BINOP_BIT_RIGHT:
// TODO make sure both operands are same type (create type cast here?)
// TODO in semantic.go, make sure rhand is *unsigned* (LLVM always treats it that way)
// TODO doc this
if lhandType.IsSigned() {
return v.builder().CreateAShr(lhand, rhand, "")
} else {
return v.builder().CreateLShr(lhand, rhand, "")
}
default:
panic("umimplented binop")
}
}
panic("unreachable")
}
