// contextFunction creates a wrapper function that
// has the same signature as the specified function,
// but has an additional first parameter that accepts
// and ignores the function context value.
//
// contextFunction must be called with a global function
// pointer.
func contextFunction(c *compiler, f *LLVMValue) *LLVMValue {
defer c.builder.SetInsertPointAtEnd(c.builder.GetInsertBlock())
resultType := c.llvmtypes.ToLLVM(f.Type())
fnptr := f.LLVMValue()
contextType := resultType.StructElementTypes()[1]
llfntyp := fnptr.Type().ElementType()
llfntyp = llvm.FunctionType(
llfntyp.ReturnType(),
append([]llvm.Type{contextType}, llfntyp.ParamTypes()...),
llfntyp.IsFunctionVarArg(),
)
wrapper := llvm.AddFunction(c.module.Module, fnptr.Name()+".ctx", llfntyp)
wrapper.SetLinkage(llvm.PrivateLinkage)
entry := llvm.AddBasicBlock(wrapper, "entry")
c.builder.SetInsertPointAtEnd(entry)
args := make([]llvm.Value, len(llfntyp.ParamTypes())-1)
for i := range args {
args[i] = wrapper.Param(i + 1)
}
result := c.builder.CreateCall(fnptr, args, "")
switch nresults := f.Type().(*types.Signature).Results().Len(); nresults {
case 0:
c.builder.CreateRetVoid()
case 1:
c.builder.CreateRet(result)
default:
results := make([]llvm.Value, nresults)
for i := range results {
results[i] = c.builder.CreateExtractValue(result, i, "")
}
c.builder.CreateAggregateRet(results)
}
return c.NewValue(wrapper, f.Type())
}
func getFflush(module llvm.Module) llvm.Value {
fflush := module.NamedFunction("fflush")
if fflush.IsNil() {
voidPtr := llvm.PointerType(llvm.Int8Type(), 0)
ftyp := llvm.FunctionType(llvm.Int32Type(), []llvm.Type{voidPtr}, false)
fflush = llvm.AddFunction(module, "fflush", ftyp)
fflush.SetFunctionCallConv(llvm.CCallConv)
}
return fflush
}
func getPrintf(module llvm.Module) llvm.Value {
printf := module.NamedFunction("printf")
if printf.IsNil() {
charPtr := llvm.PointerType(llvm.Int8Type(), 0)
ftyp := llvm.FunctionType(llvm.Int32Type(), []llvm.Type{charPtr}, true)
printf = llvm.AddFunction(module, "printf", ftyp)
printf.SetFunctionCallConv(llvm.CCallConv)
}
return printf
}
func (c *compiler) createMainFunction() error {
// In a PNaCl program (plugin), there should not be a "main.main";
// instead, we expect a "main.CreateModule" function.
// See pkg/nacl/ppapi/ppapi.go for more details.
mainMain := c.module.NamedFunction("main.main")
/*
if c.pnacl {
// PNaCl's libppapi_stub.a implements "main", which simply
// calls through to PpapiPluginMain. We define our own "main"
// so that we can capture argc/argv.
if !mainMain.IsNil() {
return fmt.Errorf("Found main.main")
}
pluginMain := c.RuntimeFunction("PpapiPluginMain", "func() int32")
// Synthesise a main which has no return value. We could cast
// PpapiPluginMain, but this is potentially unsafe as its
// calling convention is unspecified.
ftyp := llvm.FunctionType(llvm.VoidType(), nil, false)
mainMain = llvm.AddFunction(c.module.Module, "main.main", ftyp)
entry := llvm.AddBasicBlock(mainMain, "entry")
c.builder.SetInsertPointAtEnd(entry)
c.builder.CreateCall(pluginMain, nil, "")
c.builder.CreateRetVoid()
} else */{
mainMain = c.module.NamedFunction("main.main")
}
if mainMain.IsNil() {
return fmt.Errorf("Could not find main.main")
}
// runtime.main is called by main, with argc, argv, argp,
// and a pointer to main.main, which must be a niladic
// function with no result.
runtimeMain := c.runtime.main.LLVMValue()
ptrptr := llvm.PointerType(llvm.PointerType(llvm.Int8Type(), 0), 0)
ftyp := llvm.FunctionType(llvm.Int32Type(), []llvm.Type{llvm.Int32Type(), ptrptr, ptrptr}, true)
main := llvm.AddFunction(c.module.Module, "main", ftyp)
c.builder.SetCurrentDebugLocation(c.debug.MDNode(nil))
entry := llvm.AddBasicBlock(main, "entry")
c.builder.SetInsertPointAtEnd(entry)
runtimeMainParamTypes := runtimeMain.Type().ElementType().ParamTypes()
args := []llvm.Value{
main.Param(0), // argc
main.Param(1), // argv
main.Param(2), // argp
c.builder.CreateBitCast(mainMain, runtimeMainParamTypes[3], ""),
}
result := c.builder.CreateCall(runtimeMain, args, "")
c.builder.CreateRet(result)
return nil
}
func (u *unit) resolveFunction(f *ssa.Function) *LLVMValue {
if v, ok := u.globals[f]; ok {
return v
}
name := f.String()
if f.Enclosing != nil {
// Anonymous functions are not guaranteed to
// have unique identifiers at the global scope.
name = f.Enclosing.String() + ":" + name
}
// It's possible that the function already exists in the module;
// for example, if it's a runtime intrinsic that the compiler
// has already referenced.
llvmFunction := u.module.Module.NamedFunction(name)
if llvmFunction.IsNil() {
llvmType := u.llvmtypes.ToLLVM(f.Signature)
llvmType = llvmType.StructElementTypes()[0].ElementType()
if len(f.FreeVars) > 0 {
// Add an implicit first argument.
returnType := llvmType.ReturnType()
paramTypes := llvmType.ParamTypes()
vararg := llvmType.IsFunctionVarArg()
blockElementTypes := make([]llvm.Type, len(f.FreeVars))
for i, fv := range f.FreeVars {
blockElementTypes[i] = u.llvmtypes.ToLLVM(fv.Type())
}
blockType := llvm.StructType(blockElementTypes, false)
blockPtrType := llvm.PointerType(blockType, 0)
paramTypes = append([]llvm.Type{blockPtrType}, paramTypes...)
llvmType = llvm.FunctionType(returnType, paramTypes, vararg)
}
llvmFunction = llvm.AddFunction(u.module.Module, name, llvmType)
if f.Enclosing != nil {
llvmFunction.SetLinkage(llvm.PrivateLinkage)
}
u.undefinedFuncs[f] = true
}
v := u.NewValue(llvmFunction, f.Signature)
u.globals[f] = v
return v
}
func (tm *TypeMap) interfaceFuncWrapper(f llvm.Value) llvm.Value {
ftyp := f.Type().ElementType()
paramTypes := ftyp.ParamTypes()
recvType := paramTypes[0]
paramTypes[0] = llvm.PointerType(llvm.Int8Type(), 0)
newf := llvm.AddFunction(f.GlobalParent(), f.Name()+".ifn", llvm.FunctionType(
ftyp.ReturnType(),
paramTypes,
ftyp.IsFunctionVarArg(),
))
b := llvm.GlobalContext().NewBuilder()
defer b.Dispose()
entry := llvm.AddBasicBlock(newf, "entry")
b.SetInsertPointAtEnd(entry)
args := make([]llvm.Value, len(paramTypes))
for i := range paramTypes {
args[i] = newf.Param(i)
}
recvBits := int(tm.target.TypeSizeInBits(recvType))
if recvBits > 0 {
args[0] = b.CreatePtrToInt(args[0], tm.target.IntPtrType(), "")
if args[0].Type().IntTypeWidth() > recvBits {
args[0] = b.CreateTrunc(args[0], llvm.IntType(recvBits), "")
}
args[0] = coerce(b, args[0], recvType)
} else {
args[0] = llvm.ConstNull(recvType)
}
result := b.CreateCall(f, args, "")
if result.Type().TypeKind() == llvm.VoidTypeKind {
b.CreateRetVoid()
} else {
b.CreateRet(result)
}
return newf
}
func test() {
llvm.LinkInMCJIT()
llvm.InitializeNativeTarget()
llvm.InitializeNativeAsmPrinter()
mod := llvm.NewModule("fac_module")
// don't do that, because ExecutionEngine takes ownership over module
//defer mod.Dispose()
fac_args := []llvm.Type{llvm.Int32Type()}
fac_type := llvm.FunctionType(llvm.Int32Type(), fac_args, false)
fac := llvm.AddFunction(mod, "fac", fac_type)
fac.SetFunctionCallConv(llvm.CCallConv)
n := fac.Param(0)
entry := llvm.AddBasicBlock(fac, "entry")
iftrue := llvm.AddBasicBlock(fac, "iftrue")
iffalse := llvm.AddBasicBlock(fac, "iffalse")
end := llvm.AddBasicBlock(fac, "end")
builder := llvm.NewBuilder()
defer builder.Dispose()
builder.SetInsertPointAtEnd(entry)
If := builder.CreateICmp(llvm.IntEQ, n, llvm.ConstInt(llvm.Int32Type(), 0, false), "cmptmp")
builder.CreateCondBr(If, iftrue, iffalse)
builder.SetInsertPointAtEnd(iftrue)
res_iftrue := llvm.ConstInt(llvm.Int32Type(), 1, false)
builder.CreateBr(end)
builder.SetInsertPointAtEnd(iffalse)
n_minus := builder.CreateSub(n, llvm.ConstInt(llvm.Int32Type(), 1, false), "subtmp")
call_fac_args := []llvm.Value{n_minus}
call_fac := builder.CreateCall(fac, call_fac_args, "calltmp")
res_iffalse := builder.CreateMul(n, call_fac, "multmp")
builder.CreateBr(end)
builder.SetInsertPointAtEnd(end)
res := builder.CreatePHI(llvm.Int32Type(), "result")
phi_vals := []llvm.Value{res_iftrue, res_iffalse}
phi_blocks := []llvm.BasicBlock{iftrue, iffalse}
res.AddIncoming(phi_vals, phi_blocks)
builder.CreateRet(res)
err := llvm.VerifyModule(mod, llvm.ReturnStatusAction)
if err != nil {
fmt.Println(err)
return
}
engine, err := llvm.NewMCJITCompiler(mod, llvm.MCJITCompilerOptions{OptLevel: 2})
if err != nil {
fmt.Println(err)
return
}
defer engine.Dispose()
pass := llvm.NewPassManager()
defer pass.Dispose()
pass.Add(engine.TargetData())
pass.AddConstantPropagationPass()
pass.AddInstructionCombiningPass()
pass.AddPromoteMemoryToRegisterPass()
pass.AddGVNPass()
pass.AddCFGSimplificationPass()
pass.Run(mod)
mod.Dump()
exec_args := []llvm.GenericValue{llvm.NewGenericValueFromInt(llvm.Int32Type(), 10, false)}
exec_res := engine.RunFunction(fac, exec_args)
fmt.Println("-----------------------------------------")
fmt.Println("Running fac(10) with JIT...")
fmt.Printf("Result: %d\n", exec_res.Int(false))
}
// indirectFunction creates an indirect function from a
// given function and arguments, suitable for use with
// "defer" and "go".
func (c *compiler) indirectFunction(fn *LLVMValue, args []*LLVMValue) *LLVMValue {
nilarytyp := types.NewSignature(nil, nil, nil, nil, false)
if len(args) == 0 {
val := fn.LLVMValue()
ptr := c.builder.CreateExtractValue(val, 0, "")
ctx := c.builder.CreateExtractValue(val, 1, "")
fnval := llvm.Undef(c.types.ToLLVM(nilarytyp))
ptr = c.builder.CreateBitCast(ptr, fnval.Type().StructElementTypes()[0], "")
ctx = c.builder.CreateBitCast(ctx, fnval.Type().StructElementTypes()[1], "")
fnval = c.builder.CreateInsertValue(fnval, ptr, 0, "")
fnval = c.builder.CreateInsertValue(fnval, ctx, 1, "")
return c.NewValue(fnval, nilarytyp)
}
// Check if function pointer or context pointer is global/null.
fnval := fn.LLVMValue()
fnptr := fnval
var nctx int
var fnctx llvm.Value
var fnctxindex uint64
var globalfn bool
if fnptr.Type().TypeKind() == llvm.StructTypeKind {
fnptr = c.builder.CreateExtractValue(fnval, 0, "")
fnctx = c.builder.CreateExtractValue(fnval, 1, "")
globalfn = !fnptr.IsAFunction().IsNil()
if !globalfn {
nctx++
}
if !fnctx.IsNull() {
fnctxindex = uint64(nctx)
nctx++
}
} else {
// We've got a raw global function pointer. Convert to <ptr,ctx>.
fnval = llvm.ConstNull(c.types.ToLLVM(fn.Type()))
fnval = llvm.ConstInsertValue(fnval, fnptr, []uint32{0})
fn = c.NewValue(fnval, fn.Type())
fnctx = llvm.ConstExtractValue(fnval, []uint32{1})
globalfn = true
}
i8ptr := llvm.PointerType(llvm.Int8Type(), 0)
llvmargs := make([]llvm.Value, len(args)+nctx)
llvmargtypes := make([]llvm.Type, len(args)+nctx)
for i, arg := range args {
llvmargs[i+nctx] = arg.LLVMValue()
llvmargtypes[i+nctx] = llvmargs[i+nctx].Type()
}
if !globalfn {
llvmargtypes[0] = fnptr.Type()
llvmargs[0] = fnptr
}
if !fnctx.IsNull() {
llvmargtypes[fnctxindex] = fnctx.Type()
llvmargs[fnctxindex] = fnctx
}
// TODO(axw) investigate an option for go statements
// to allocate argument structure on the stack in the
// initiator, and block until the spawned goroutine
// has loaded the arguments from it.
structtyp := llvm.StructType(llvmargtypes, false)
argstruct := c.createTypeMalloc(structtyp)
for i, llvmarg := range llvmargs {
argptr := c.builder.CreateGEP(argstruct, []llvm.Value{
llvm.ConstInt(llvm.Int32Type(), 0, false),
llvm.ConstInt(llvm.Int32Type(), uint64(i), false)}, "")
c.builder.CreateStore(llvmarg, argptr)
}
// Create a function that will take a pointer to a structure of the type
// defined above, or no parameters if there are none to pass.
fntype := llvm.FunctionType(llvm.VoidType(), []llvm.Type{argstruct.Type()}, false)
indirectfn := llvm.AddFunction(c.module.Module, "", fntype)
i8argstruct := c.builder.CreateBitCast(argstruct, i8ptr, "")
currblock := c.builder.GetInsertBlock()
c.builder.SetInsertPointAtEnd(llvm.AddBasicBlock(indirectfn, "entry"))
argstruct = indirectfn.Param(0)
newargs := make([]*LLVMValue, len(args))
for i := range llvmargs[nctx:] {
argptr := c.builder.CreateGEP(argstruct, []llvm.Value{
llvm.ConstInt(llvm.Int32Type(), 0, false),
llvm.ConstInt(llvm.Int32Type(), uint64(i+nctx), false)}, "")
newargs[i] = c.NewValue(c.builder.CreateLoad(argptr, ""), args[i].Type())
}
// Unless we've got a global function, extract the
// function pointer from the context.
if !globalfn {
fnval = llvm.Undef(fnval.Type())
fnptrptr := c.builder.CreateGEP(argstruct, []llvm.Value{
llvm.ConstInt(llvm.Int32Type(), 0, false),
llvm.ConstInt(llvm.Int32Type(), 0, false)}, "")
fnptr = c.builder.CreateLoad(fnptrptr, "")
fnval = c.builder.CreateInsertValue(fnval, fnptr, 0, "")
}
if !fnctx.IsNull() {
fnctxptr := c.builder.CreateGEP(argstruct, []llvm.Value{
llvm.ConstInt(llvm.Int32Type(), 0, false),
llvm.ConstInt(llvm.Int32Type(), fnctxindex, false)}, "")
fnctx = c.builder.CreateLoad(fnctxptr, "")
fnval = c.builder.CreateInsertValue(fnval, fnctx, 1, "")
fn = c.NewValue(fnval, fn.Type())
}
c.createCall(fn, newargs)
// Indirect function calls' return values are always ignored.
c.builder.CreateRetVoid()
c.builder.SetInsertPointAtEnd(currblock)
fnval = llvm.Undef(c.types.ToLLVM(nilarytyp))
indirectfn = c.builder.CreateBitCast(indirectfn, fnval.Type().StructElementTypes()[0], "")
fnval = c.builder.CreateInsertValue(fnval, indirectfn, 0, "")
fnval = c.builder.CreateInsertValue(fnval, i8argstruct, 1, "")
fn = c.NewValue(fnval, nilarytyp)
return fn
}
// prepareCall returns the evaluated function and arguments.
//
// For builtins that may not be used in go/defer, prepareCall
// will emits inline code. In this case, prepareCall returns
// nil for fn and args, and returns a non-nil value for result.
func (fr *frame) prepareCall(instr ssa.CallInstruction) (fn *LLVMValue, args []*LLVMValue, result *LLVMValue) {
call := instr.Common()
args = make([]*LLVMValue, len(call.Args))
for i, arg := range call.Args {
args[i] = fr.value(arg)
}
if call.IsInvoke() {
fn := fr.interfaceMethod(fr.value(call.Value), call.Method)
return fn, args, nil
}
switch v := call.Value.(type) {
case *ssa.Builtin:
// handled below
case *ssa.Function:
// Function handled specially; value() will convert
// a function to one with a context argument.
fn = fr.resolveFunction(v)
pair := llvm.ConstNull(fr.llvmtypes.ToLLVM(fn.Type()))
pair = llvm.ConstInsertValue(pair, fn.LLVMValue(), []uint32{0})
fn = fr.NewValue(pair, fn.Type())
return fn, args, nil
default:
fn = fr.value(call.Value)
return fn, args, nil
}
// Builtins may only be used in calls (i.e. can't be assigned),
// and only print[ln], panic and recover may be used in go/defer.
builtin := call.Value.(*ssa.Builtin)
switch builtin.Name() {
case "print", "println":
// print/println generates a call-site specific anonymous
// function to print the values. It's not inline because
// print/println may be deferred.
params := make([]*types.Var, len(call.Args))
for i, arg := range call.Args {
// make sure to use args[i].Type(), not call.Args[i].Type(),
// as the evaluated expression converts untyped.
params[i] = types.NewParam(arg.Pos(), nil, arg.Name(), args[i].Type())
}
sig := types.NewSignature(nil, nil, types.NewTuple(params...), nil, false)
llfntyp := fr.llvmtypes.ToLLVM(sig)
llfnptr := llvm.AddFunction(fr.module.Module, "", llfntyp.StructElementTypes()[0].ElementType())
currBlock := fr.builder.GetInsertBlock()
entry := llvm.AddBasicBlock(llfnptr, "entry")
fr.builder.SetInsertPointAtEnd(entry)
internalArgs := make([]Value, len(args))
for i, arg := range args {
internalArgs[i] = fr.NewValue(llfnptr.Param(i), arg.Type())
}
fr.printValues(builtin.Name() == "println", internalArgs...)
fr.builder.CreateRetVoid()
fr.builder.SetInsertPointAtEnd(currBlock)
return fr.NewValue(llfnptr, sig), args, nil
case "panic":
panic("TODO: panic")
case "recover":
// TODO(axw) determine number of frames to skip in pc check
indirect := fr.NewValue(llvm.ConstNull(llvm.Int32Type()), types.Typ[types.Int32])
return fr.runtime.recover_, []*LLVMValue{indirect}, nil
case "append":
return nil, nil, fr.callAppend(args[0], args[1])
case "close":
return fr.runtime.chanclose, args, nil
case "cap":
return nil, nil, fr.callCap(args[0])
case "len":
return nil, nil, fr.callLen(args[0])
case "copy":
return nil, nil, fr.callCopy(args[0], args[1])
case "delete":
fr.callDelete(args[0], args[1])
return nil, nil, nil
case "real":
return nil, nil, args[0].extractComplexComponent(0)
case "imag":
return nil, nil, args[0].extractComplexComponent(1)
case "complex":
r := args[0].LLVMValue()
i := args[1].LLVMValue()
typ := instr.Value().Type()
cmplx := llvm.Undef(fr.llvmtypes.ToLLVM(typ))
cmplx = fr.builder.CreateInsertValue(cmplx, r, 0, "")
cmplx = fr.builder.CreateInsertValue(cmplx, i, 1, "")
return nil, nil, fr.NewValue(cmplx, typ)
default:
panic("unimplemented: " + builtin.Name())
}
}
