diff --git a/ssa/coro.go b/ssa/coro.go
new file mode 100644
index 00000000..d6183f93
--- /dev/null
+++ b/ssa/coro.go
@@ -0,0 +1,486 @@
+/*
+ * Copyright (c) 2024 The GoPlus Authors (goplus.org). All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ssa
+
+import (
+	"go/token"
+	"go/types"
+)
+
+// declare void @llvm.coro.destroy(i8*)
+func (p Program) tyCoDestroy() *types.Signature {
+	if p.coDestroyTy == nil {
+		i8Ptr := types.NewParam(token.NoPos, nil, "", p.VoidPtr().raw.Type)
+		params := types.NewTuple(i8Ptr)
+		p.coDestroyTy = types.NewSignatureType(nil, nil, nil, params, nil, false)
+	}
+	return p.coDestroyTy
+}
+
+// declare void @llvm.coro.resume(i8*)
+func (p Program) tyCoResume() *types.Signature {
+	if p.coResumeTy == nil {
+		i8Ptr := types.NewParam(token.NoPos, nil, "", p.VoidPtr().raw.Type)
+		params := types.NewTuple(i8Ptr)
+		p.coResumeTy = types.NewSignatureType(nil, nil, nil, params, nil, false)
+	}
+	return p.coResumeTy
+}
+
+// declare i1 @llvm.coro.done(ptr <handle>)
+func (p Program) tyCoDone() *types.Signature {
+	if p.coDoneTy == nil {
+		i8Ptr := types.NewParam(token.NoPos, nil, "", p.VoidPtr().raw.Type)
+		params := types.NewTuple(i8Ptr)
+		results := types.NewTuple(types.NewParam(token.NoPos, nil, "", p.Bool().raw.Type))
+		p.coDoneTy = types.NewSignatureType(nil, nil, nil, params, results, false)
+	}
+	return p.coDoneTy
+}
+
+// declare ptr @llvm.coro.promise(ptr <ptr>, i32 <alignment>, i1 <from>)
+func (p Program) tyCoPromise() *types.Signature {
+	if p.coPromiseTy == nil {
+		i8Ptr := types.NewParam(token.NoPos, nil, "", p.VoidPtr().raw.Type)
+		i32 := types.NewParam(token.NoPos, nil, "", p.Int32().raw.Type)
+		boolParam := types.NewParam(token.NoPos, nil, "", p.Bool().raw.Type)
+		params := types.NewTuple(i8Ptr, i32, boolParam)
+		results := types.NewTuple(i8Ptr)
+		p.coPromiseTy = types.NewSignatureType(nil, nil, nil, params, results, false)
+	}
+	return p.coPromiseTy
+}
+
+// declare i32 @llvm.coro.size.i32()
+func (p Program) tyCoSizeI32() *types.Signature {
+	if p.coSizeI32Ty == nil {
+		results := types.NewTuple(types.NewParam(token.NoPos, nil, "", p.Int32().raw.Type))
+		p.coSizeI32Ty = types.NewSignatureType(nil, nil, nil, nil, results, false)
+	}
+	return p.coSizeI32Ty
+}
+
+// declare i32 @llvm.coro.size.i64()
+func (p Program) tyCoSizeI64() *types.Signature {
+	if p.coSizeI64Ty == nil {
+		results := types.NewTuple(types.NewParam(token.NoPos, nil, "", p.Int64().raw.Type))
+		p.coSizeI64Ty = types.NewSignatureType(nil, nil, nil, nil, results, false)
+	}
+	return p.coSizeI64Ty
+}
+
+// declare i32 @llvm.coro.align.i32()
+func (p Program) tyCoAlignI32() *types.Signature {
+	if p.coAlignI32Ty == nil {
+		results := types.NewTuple(types.NewParam(token.NoPos, nil, "", p.Int32().raw.Type))
+		p.coAlignI32Ty = types.NewSignatureType(nil, nil, nil, nil, results, false)
+	}
+	return p.coAlignI32Ty
+}
+
+// declare i64 @llvm.coro.align.i64()
+func (p Program) tyCoAlignI64() *types.Signature {
+	if p.coAlignI64Ty == nil {
+		results := types.NewTuple(types.NewParam(token.NoPos, nil, "", p.Int64().raw.Type))
+		p.coAlignI64Ty = types.NewSignatureType(nil, nil, nil, nil, results, false)
+	}
+	return p.coAlignI64Ty
+}
+
+// declare i8* @llvm.coro.begin(token, i8*)
+func (p Program) tyCoBegin() *types.Signature {
+	if p.coBeginTy == nil {
+		tokenParam := types.NewParam(token.NoPos, nil, "", p.Token().raw.Type)
+		i8Ptr := types.NewParam(token.NoPos, nil, "", p.VoidPtr().raw.Type)
+		params := types.NewTuple(tokenParam, i8Ptr)
+		results := types.NewTuple(i8Ptr)
+		p.coBeginTy = types.NewSignatureType(nil, nil, nil, params, results, false)
+	}
+	return p.coBeginTy
+}
+
+// declare i8* @llvm.coro.free(token, i8*)
+func (p Program) tyCoFree() *types.Signature {
+	if p.coFreeTy == nil {
+		tokenParam := types.NewParam(token.NoPos, nil, "", p.Token().raw.Type)
+		i8Ptr := types.NewParam(token.NoPos, nil, "", p.VoidPtr().raw.Type)
+		params := types.NewTuple(tokenParam, i8Ptr)
+		results := types.NewTuple(i8Ptr)
+		p.coFreeTy = types.NewSignatureType(nil, nil, nil, params, results, false)
+	}
+	return p.coFreeTy
+}
+
+// declare i1 @llvm.coro.alloc(token)
+func (p Program) tyCoAlloc() *types.Signature {
+	if p.coAllocTy == nil {
+		tokenParam := types.NewParam(token.NoPos, nil, "", p.Token().raw.Type)
+		params := types.NewTuple(tokenParam)
+		boolParam := types.NewParam(token.NoPos, nil, "", p.Bool().raw.Type)
+		results := types.NewTuple(boolParam)
+		p.coAllocTy = types.NewSignatureType(nil, nil, nil, params, results, false)
+	}
+	return p.coAllocTy
+}
+
+// declare ptr @llvm.coro.noop()
+func (p Program) tyCoNoop() *types.Signature {
+	if p.coNoopTy == nil {
+		results := types.NewTuple(types.NewParam(token.NoPos, nil, "", p.VoidPtr().raw.Type))
+		p.coNoopTy = types.NewSignatureType(nil, nil, nil, nil, results, false)
+	}
+	return p.coNoopTy
+}
+
+// declare ptr @llvm.coro.frame()
+func (p Program) tyCoFrame() *types.Signature {
+	if p.coFrameTy == nil {
+		results := types.NewTuple(types.NewParam(token.NoPos, nil, "", p.VoidPtr().raw.Type))
+		p.coFrameTy = types.NewSignatureType(nil, nil, nil, nil, results, false)
+	}
+	return p.coFrameTy
+}
+
+// declare token @llvm.coro.id(i32, i8*, i8*, i8*)
+func (p Program) tyCoID() *types.Signature {
+	if p.coIDTy == nil {
+		i32 := types.NewParam(token.NoPos, nil, "", p.Int32().raw.Type)
+		i8Ptr := types.NewParam(token.NoPos, nil, "", p.VoidPtr().raw.Type)
+		params := types.NewTuple(i32, i8Ptr, i8Ptr, i8Ptr)
+		tokenParam := types.NewParam(token.NoPos, nil, "", p.Token().raw.Type)
+		results := types.NewTuple(tokenParam)
+		p.coIDTy = types.NewSignatureType(nil, nil, nil, params, results, false)
+	}
+	return p.coIDTy
+}
+
+// declare token @llvm.coro.id.async(i32 <context size>, i32 <align>, ptr <context arg>, ptr <async function pointer>)
+func (p Program) tyCoIDAsync() *types.Signature {
+	if p.coIDAsyncTy == nil {
+		i32 := types.NewParam(token.NoPos, nil, "", p.Int32().raw.Type)
+		i8Ptr := types.NewParam(token.NoPos, nil, "", p.VoidPtr().raw.Type)
+		params := types.NewTuple(i32, i32, i8Ptr, i8Ptr)
+		tokenParam := types.NewParam(token.NoPos, nil, "", p.Token().raw.Type)
+		results := types.NewTuple(tokenParam)
+		p.coIDAsyncTy = types.NewSignatureType(nil, nil, nil, params, results, false)
+	}
+	return p.coIDAsyncTy
+}
+
+// declare token @llvm.coro.id.retcon(i32 <size>, i32 <align>, ptr <buffer>, ptr <continuation prototype>, ptr <alloc>, ptr <dealloc>)
+func (p Program) tyCoIDRetcon() *types.Signature {
+	if p.coIDRetconTy == nil {
+		i32 := types.NewParam(token.NoPos, nil, "", p.Int32().raw.Type)
+		i8Ptr := types.NewParam(token.NoPos, nil, "", p.VoidPtr().raw.Type)
+		params := types.NewTuple(i32, i32, i8Ptr, i8Ptr, i8Ptr, i8Ptr)
+		tokenParam := types.NewParam(token.NoPos, nil, "", p.Token().raw.Type)
+		results := types.NewTuple(tokenParam)
+		p.coIDRetconTy = types.NewSignatureType(nil, nil, nil, params, results, false)
+	}
+	return p.coIDRetconTy
+}
+
+// declare token @llvm.coro.id.retcon.once(i32 <size>, i32 <align>, ptr <buffer>, ptr <prototype>, ptr <alloc>, ptr <dealloc>)
+func (p Program) tyCoIDRetconOnce() *types.Signature {
+	if p.coIDRetconOnceTy == nil {
+		i32 := types.NewParam(token.NoPos, nil, "", p.Int32().raw.Type)
+		i8Ptr := types.NewParam(token.NoPos, nil, "", p.VoidPtr().raw.Type)
+		params := types.NewTuple(i32, i32, i8Ptr, i8Ptr, i8Ptr, i8Ptr)
+		tokenParam := types.NewParam(token.NoPos, nil, "", p.Token().raw.Type)
+		results := types.NewTuple(tokenParam)
+		p.coIDRetconOnceTy = types.NewSignatureType(nil, nil, nil, params, results, false)
+	}
+	return p.coIDRetconOnceTy
+}
+
+// declare i1 @llvm.coro.end(i8*, i1, token)
+func (p Program) tyCoEnd() *types.Signature {
+	if p.coEndTy == nil {
+		i8Ptr := types.NewParam(token.NoPos, nil, "", p.VoidPtr().raw.Type)
+		boolParam := types.NewParam(token.NoPos, nil, "", p.Bool().raw.Type)
+		tokenParam := types.NewParam(token.NoPos, nil, "", p.Token().raw.Type)
+		params := types.NewTuple(i8Ptr, boolParam, tokenParam)
+		results := types.NewTuple(boolParam)
+		p.coEndTy = types.NewSignatureType(nil, nil, nil, params, results, false)
+	}
+	return p.coEndTy
+}
+
+// TODO(lijie): varargs
+// declare token @llvm.coro.end.results(...)
+func (p Program) tyCoEndResults() *types.Signature {
+	panic("not implemented")
+}
+
+// TODO(lijie): varargs
+// declare i1 @llvm.coro.end.async(ptr <handle>, i1 <unwind>, ...)
+func (p Program) tyCoEndAsync() *types.Signature {
+	panic("not implemented")
+}
+
+// declare i8 @llvm.coro.suspend(token <save>, i1 <final>)
+func (p Program) tyCoSuspend() *types.Signature {
+	if p.coSuspendTy == nil {
+		tokenParam := types.NewParam(token.NoPos, nil, "", p.Token().raw.Type)
+		boolParam := types.NewParam(token.NoPos, nil, "", p.Bool().raw.Type)
+		params := types.NewTuple(tokenParam, boolParam)
+		paramByte := types.NewParam(token.NoPos, nil, "", p.Byte().raw.Type)
+		results := types.NewTuple(paramByte)
+		p.coSuspendTy = types.NewSignatureType(nil, nil, nil, params, results, false)
+	}
+	return p.coSuspendTy
+}
+
+// declare token @llvm.coro.save(ptr <handle>)
+func (p Program) tyCoSave() *types.Signature {
+	if p.coSaveTy == nil {
+		i8Ptr := types.NewParam(token.NoPos, nil, "", p.VoidPtr().raw.Type)
+		params := types.NewTuple(i8Ptr)
+		tokenParam := types.NewParam(token.NoPos, nil, "", p.Token().raw.Type)
+		results := types.NewTuple(tokenParam)
+		p.coSaveTy = types.NewSignatureType(nil, nil, nil, params, results, false)
+	}
+	return p.coSaveTy
+}
+
+// TODO(lijie): varargs
+// declare {ptr, ptr, ptr} @llvm.coro.suspend.async(ptr <resume function>, ptr <context projection function>, ... <function to call> ... <arguments to function>)
+func (p Program) tyCoSuspendAsync() *types.Signature {
+	panic("not implemented")
+}
+
+// declare ptr @llvm.coro.prepare.async(ptr <coroutine function>)
+func (p Program) tyCoPrepareAsync() *types.Signature {
+	if p.coPrepareAsyncTy == nil {
+		i8Ptr := types.NewParam(token.NoPos, nil, "", p.VoidPtr().raw.Type)
+		params := types.NewTuple(i8Ptr)
+		results := types.NewTuple(i8Ptr)
+		p.coPrepareAsyncTy = types.NewSignatureType(nil, nil, nil, params, results, false)
+	}
+	return p.coPrepareAsyncTy
+}
+
+// declare i1 @llvm.coro.suspend.retcon(...)
+func (p Program) tyCoSuspendRetcon() *types.Signature {
+	panic("not implemented")
+}
+
+// declare void @await_suspend_function(ptr %awaiter, ptr %hdl)
+func (p Program) tyCoAwaitSuspendFunction() *types.Signature {
+	if p.coAwaitSuspendFunctionTy == nil {
+		i8Ptr := types.NewParam(token.NoPos, nil, "", p.VoidPtr().raw.Type)
+		params := types.NewTuple(i8Ptr, i8Ptr)
+		p.coAwaitSuspendFunctionTy = types.NewSignatureType(nil, nil, nil, params, nil, false)
+	}
+	return p.coAwaitSuspendFunctionTy
+}
+
+// declare void @llvm.coro.await.suspend.void(ptr <awaiter>, ptr <handle>, ptr <await_suspend_function>)
+func (p Program) tyCoAwaitSuspendVoid() *types.Signature {
+	if p.coAwaitSuspendVoidTy == nil {
+		i8Ptr := types.NewParam(token.NoPos, nil, "", p.VoidPtr().raw.Type)
+		params := types.NewTuple(i8Ptr, i8Ptr, i8Ptr)
+		p.coAwaitSuspendVoidTy = types.NewSignatureType(nil, nil, nil, params, nil, false)
+	}
+	return p.coAwaitSuspendVoidTy
+}
+
+// declare i1 @llvm.coro.await.suspend.bool(ptr <awaiter>, ptr <handle>, ptr <await_suspend_function>)
+func (p Program) tyCoAwaitSuspendBool() *types.Signature {
+	if p.coAwaitSuspendBoolTy == nil {
+		i8Ptr := types.NewParam(token.NoPos, nil, "", p.VoidPtr().raw.Type)
+		params := types.NewTuple(i8Ptr, i8Ptr, i8Ptr)
+		results := types.NewTuple(types.NewParam(token.NoPos, nil, "", p.Bool().raw.Type))
+		p.coAwaitSuspendBoolTy = types.NewSignatureType(nil, nil, nil, params, results, false)
+	}
+	return p.coAwaitSuspendBoolTy
+}
+
+// declare void @llvm.coro.await.suspend.handle(ptr <awaiter>, ptr <handle>, ptr <await_suspend_function>)
+func (p Program) tyCoAwaitSuspendHandle() *types.Signature {
+	if p.coAwaitSuspendHandleTy == nil {
+		i8Ptr := types.NewParam(token.NoPos, nil, "", p.VoidPtr().raw.Type)
+		params := types.NewTuple(i8Ptr, i8Ptr, i8Ptr)
+		p.coAwaitSuspendHandleTy = types.NewSignatureType(nil, nil, nil, params, nil, false)
+	}
+	return p.coAwaitSuspendHandleTy
+}
+
+// -----------------------------------------------------------------------------
+
+// declare void @llvm.coro.destroy(ptr <handle>)
+func (b Builder) CoDestroy(hdl Expr) {
+	fn := b.Pkg.cFunc("llvm.coro.destroy", b.Prog.tyCoDestroy())
+	b.Call(fn, hdl)
+}
+
+// declare void @llvm.coro.resume(ptr <handle>)
+func (b Builder) CoResume(hdl Expr) {
+	fn := b.Pkg.cFunc("llvm.coro.resume", b.Prog.tyCoResume())
+	b.Call(fn, hdl)
+}
+
+// declare i1 @llvm.coro.done(ptr <handle>)
+func (b Builder) CoDone(hdl Expr) Expr {
+	fn := b.Pkg.cFunc("llvm.coro.done", b.Prog.tyCoDone())
+	return b.Call(fn, hdl)
+}
+
+// declare ptr @llvm.coro.promise(ptr <ptr>, i32 <alignment>, i1 <from>)
+func (b Builder) CoPromise(ptr, align, from Expr) Expr {
+	fn := b.Pkg.cFunc("llvm.coro.promise", b.Prog.tyCoPromise())
+	return b.Call(fn, ptr, align, from)
+}
+
+// declare i32 @llvm.coro.size.i32()
+func (b Builder) CoSizeI32() Expr {
+	fn := b.Pkg.cFunc("llvm.coro.size.i32", b.Prog.tyCoSizeI32())
+	return b.Call(fn)
+}
+
+// declare i64 @llvm.coro.size.i64()
+func (b Builder) CoSizeI64() Expr {
+	fn := b.Pkg.cFunc("llvm.coro.size.i64", b.Prog.tyCoSizeI64())
+	return b.Call(fn)
+}
+
+// declare i32 @llvm.coro.align.i32()
+func (b Builder) CoAlignI32() Expr {
+	fn := b.Pkg.cFunc("llvm.coro.align.i32", b.Prog.tyCoAlignI32())
+	return b.Call(fn)
+}
+
+// declare i64 @llvm.coro.align.i64()
+func (b Builder) CoAlignI64() Expr {
+	fn := b.Pkg.cFunc("llvm.coro.align.i64", b.Prog.tyCoAlignI64())
+	return b.Call(fn)
+}
+
+// declare ptr @llvm.coro.begin(token <id>, ptr <mem>)
+func (b Builder) CoBegin(id, mem Expr) Expr {
+	fn := b.Pkg.cFunc("llvm.coro.begin", b.Prog.tyCoBegin())
+	return b.Call(fn, id, mem)
+}
+
+// declare ptr @llvm.coro.free(token %id, ptr <frame>)
+func (b Builder) CoFree(id, frame Expr) Expr {
+	fn := b.Pkg.cFunc("llvm.coro.free", b.Prog.tyCoFree())
+	return b.Call(fn, id, frame)
+}
+
+// declare i1 @llvm.coro.alloc(token <id>)
+func (b Builder) CoAlloc(id Expr) Expr {
+	fn := b.Pkg.cFunc("llvm.coro.alloc", b.Prog.tyCoAlloc())
+	return b.Call(fn, id)
+}
+
+// declare ptr @llvm.coro.noop()
+func (b Builder) CoNoop() Expr {
+	fn := b.Pkg.cFunc("llvm.coro.noop", b.Prog.tyCoNoop())
+	return b.Call(fn)
+}
+
+// declare ptr @llvm.coro.frame()
+func (b Builder) CoFrame() Expr {
+	fn := b.Pkg.cFunc("llvm.coro.frame", b.Prog.tyCoFrame())
+	return b.Call(fn)
+}
+
+// declare token @llvm.coro.id(i32 <align>, ptr <promise>, ptr <coroaddr>, ptr <fnaddrs>)
+func (b Builder) CoID(align Expr, promise, coroAddr, fnAddrs Expr) Expr {
+	fn := b.Pkg.cFunc("llvm.coro.id", b.Prog.tyCoID())
+	return b.Call(fn, align, promise, coroAddr, fnAddrs)
+}
+
+// declare token @llvm.coro.id.async(i32 <context size>, i32 <align>, ptr <context arg>, ptr <async function pointer>)
+func (b Builder) CoIDAsync(contextSize, align, contextArg, asyncFnPtr Expr) Expr {
+	fn := b.Pkg.cFunc("llvm.coro.id.async", b.Prog.tyCoIDAsync())
+	return b.Call(fn, contextSize, align, contextArg, asyncFnPtr)
+}
+
+// declare token @llvm.coro.id.retcon(i32 <size>, i32 <align>, ptr <buffer>, ptr <continuation prototype>, ptr <alloc>, ptr <dealloc>)
+func (b Builder) CoIDRetcon(size, align, buffer, contProto, alloc, dealloc Expr) Expr {
+	fn := b.Pkg.cFunc("llvm.coro.id.retcon", b.Prog.tyCoIDRetcon())
+	return b.Call(fn, size, align, buffer, contProto, alloc, dealloc)
+}
+
+// declare token @llvm.coro.id.retcon.once(i32 <size>, i32 <align>, ptr <buffer>, ptr <prototype>, ptr <alloc>, ptr <dealloc>)
+func (b Builder) CoIDRetconOnce(size, align, buffer, prototype, alloc, dealloc Expr) Expr {
+	fn := b.Pkg.cFunc("llvm.coro.id.retcon.once", b.Prog.tyCoIDRetconOnce())
+	return b.Call(fn, size, align, buffer, prototype, alloc, dealloc)
+}
+
+// declare i1 @llvm.coro.end(ptr <handle>, i1 <unwind>, token <result.token>)
+func (b Builder) CoEnd(hdl Expr, unwind Expr, resultToken Expr) Expr {
+	fn := b.Pkg.cFunc("llvm.coro.end", b.Prog.tyCoEnd())
+	return b.Call(fn, hdl, unwind, resultToken)
+}
+
+// declare token @llvm.coro.end.results(...)
+func (b Builder) CoEndResults(args []Expr) Expr {
+	fn := b.Pkg.cFunc("llvm.coro.end.results", b.Prog.tyCoEndResults())
+	return b.Call(fn, args...)
+}
+
+// declare i1 @llvm.coro.end.async(ptr <handle>, i1 <unwind>, ...)
+func (b Builder) CoEndAsync(handle, unwind Expr, args ...Expr) Expr {
+	fn := b.Pkg.cFunc("llvm.coro.end.async", b.Prog.tyCoEndAsync())
+	args = append([]Expr{handle, unwind}, args...)
+	return b.Call(fn, args...)
+}
+
+// declare i8 @llvm.coro.suspend(token <save>, i1 <final>)
+func (b Builder) CoSuspend(save, final Expr) Expr {
+	fn := b.Pkg.cFunc("llvm.coro.suspend", b.Prog.tyCoSuspend())
+	return b.Call(fn, save, final)
+}
+
+// declare token @llvm.coro.save(ptr <handle>)
+func (b Builder) CoSave(hdl Expr) Expr {
+	fn := b.Pkg.cFunc("llvm.coro.save", b.Prog.tyCoSave())
+	return b.Call(fn, hdl)
+}
+
+// declare ptr @llvm.coro.prepare.async(ptr <coroutine function>)
+func (b Builder) CoPrepareAsync(f Expr) Expr {
+	fn := b.Pkg.cFunc("llvm.coro.prepare.async", b.Prog.tyCoPrepareAsync())
+	return b.Call(fn, f)
+}
+
+// declare i1 @llvm.coro.suspend.retcon(...)
+func (b Builder) CoSuspendRetcon(args []Expr) Expr {
+	fn := b.Pkg.cFunc("llvm.coro.suspend.retcon", b.Prog.tyCoSuspendRetcon())
+	return b.Call(fn, args...)
+}
+
+// declare void @llvm.coro.await.suspend.void(ptr <awaiter>, ptr <handle>, ptr <await_suspend_function>)
+func (b Builder) CoAwaitSuspendVoid(awaiter, handle, f Expr) {
+	fn := b.Pkg.cFunc("llvm.coro.await.suspend.void", b.Prog.tyCoAwaitSuspendVoid())
+	b.Call(fn, awaiter, handle, f)
+}
+
+// declare i1 @llvm.coro.await.suspend.bool(ptr <awaiter>, ptr <handle>, ptr <await_suspend_function>)
+func (b Builder) CoAwaitSuspendBool(awaiter, handle, f Expr) Expr {
+	fn := b.Pkg.cFunc("llvm.coro.await.suspend.bool", b.Prog.tyCoAwaitSuspendBool())
+	return b.Call(fn, awaiter, handle, f)
+}
+
+// declare void @llvm.coro.await.suspend.handle(ptr <awaiter>, ptr <handle>, ptr <await_suspend_function>)
+func (b Builder) CoAwaitSuspendHandle(awaiter, handle, f Expr) {
+	fn := b.Pkg.cFunc("llvm.coro.await.suspend.handle", b.Prog.tyCoAwaitSuspendHandle())
+	b.Call(fn, awaiter, handle, f)
+}
diff --git a/ssa/package.go b/ssa/package.go
index 382ef365..7be6d901 100644
--- a/ssa/package.go
+++ b/ssa/package.go
@@ -135,6 +135,8 @@ type aProgram struct {
 	rtMapTy    llvm.Type
 	rtChanTy   llvm.Type
 
+	tokenType llvm.Type
+
 	anyTy     Type
 	voidTy    Type
 	voidPtr   Type
@@ -165,6 +167,8 @@ type aProgram struct {
 	deferTy   Type
 	deferPtr  Type
 
+	tokenTy Type
+
 	pyImpTy      *types.Signature
 	pyNewList    *types.Signature
 	pyListSetI   *types.Signature
@@ -188,6 +192,39 @@ type aProgram struct {
 	sigsetjmpTy *types.Signature
 	sigljmpTy   *types.Signature
 
+	// coroutine manipulation intrinsics (ordered by LLVM coroutine doc)
+	coDestroyTy *types.Signature
+	coResumeTy  *types.Signature
+	coDoneTy    *types.Signature
+	coPromiseTy *types.Signature
+
+	// coroutine structure intrinsics (ordered by LLVM coroutine doc)
+	coSizeI32Ty              *types.Signature
+	coSizeI64Ty              *types.Signature
+	coAlignI32Ty             *types.Signature
+	coAlignI64Ty             *types.Signature
+	coBeginTy                *types.Signature
+	coFreeTy                 *types.Signature
+	coAllocTy                *types.Signature
+	coNoopTy                 *types.Signature
+	coFrameTy                *types.Signature
+	coIDTy                   *types.Signature
+	coIDAsyncTy              *types.Signature
+	coIDRetconTy             *types.Signature
+	coIDRetconOnceTy         *types.Signature
+	coEndTy                  *types.Signature
+	coEndResultsTy           *types.Signature
+	coEndAsyncTy             *types.Signature
+	coSuspendTy              *types.Signature
+	coSaveTy                 *types.Signature
+	coSuspendAsyncTy         *types.Signature
+	coPrepareAsyncTy         *types.Signature
+	coSuspendRetconTy        *types.Signature
+	coAwaitSuspendFunctionTy *types.Signature
+	coAwaitSuspendVoidTy     *types.Signature
+	coAwaitSuspendBoolTy     *types.Signature
+	coAwaitSuspendHandleTy   *types.Signature
+
 	paramObjPtr_ *types.Var
 
 	ptrSize int
@@ -437,6 +474,13 @@ func (p Program) Any() Type {
 	return p.anyTy
 }
 
+func (p Program) Token() Type {
+	if p.tokenTy == nil {
+		p.tokenTy = &aType{p.tyToken(), rawType{types.Typ[types.Invalid]}, vkInvalid}
+	}
+	return p.tokenTy
+}
+
 /*
 // Eface returns the empty interface type.
 // It is equivalent to Any.
diff --git a/ssa/type.go b/ssa/type.go
index 5e2dcf88..9ab79f18 100644
--- a/ssa/type.go
+++ b/ssa/type.go
@@ -58,6 +58,7 @@ const (
 	vkIface
 	vkStruct
 	vkChan
+	vkToken
 )
 
 // -----------------------------------------------------------------------------
@@ -282,6 +283,13 @@ func (p Program) tyInt() llvm.Type {
 	return p.intType
 }
 
+func (p Program) tyToken() llvm.Type {
+	if p.tokenType.IsNil() {
+		p.tokenType = p.ctx.TokenType()
+	}
+	return p.tokenType
+}
+
 func llvmIntType(ctx llvm.Context, size int) llvm.Type {
 	if size <= 4 {
 		return ctx.Int32Type()
@@ -362,6 +370,9 @@ func (p Program) toType(raw types.Type) Type {
 			return &aType{p.rtString(), typ, vkString}
 		case types.UnsafePointer:
 			return &aType{p.tyVoidPtr(), typ, vkPtr}
+		// TODO(lijie): temporary solution, should be replaced by a proper type
+		case types.Invalid:
+			return &aType{p.tyToken(), typ, vkInvalid}
 		}
 	case *types.Pointer:
 		elem := p.rawType(t.Elem())
@@ -444,7 +455,8 @@ func (p Program) toLLVMTypes(t *types.Tuple, n int) (ret []llvm.Type) {
 	if n > 0 {
 		ret = make([]llvm.Type, n)
 		for i := 0; i < n; i++ {
-			ret[i] = p.rawType(t.At(i).Type()).ll
+			pt := t.At(i)
+			ret[i] = p.rawType(pt.Type()).ll
 		}
 	}
 	return