cgo: support macros

cl/compile.go

@@ -189,8 +189,17 @@ var (
 	argvTy = types.NewPointer(types.NewPointer(types.Typ[types.Int8]))
 )
 
-func isCgoCfunc(f *ssa.Function) bool {
-	return strings.HasPrefix(f.Name(), "_Cfunc_")
+func isCgoCfuncOrCmacro(f *ssa.Function) bool {
+	name := f.Name()
+	return isCgoCfunc(name) || isCgoCmacro(name)
+}
+
+func isCgoCfunc(name string) bool {
+	return strings.HasPrefix(name, "_Cfunc_")
+}
+
+func isCgoCmacro(name string) bool {
+	return strings.HasPrefix(name, "_Cmacro_")
 }
 
 func (p *context) compileFuncDecl(pkg llssa.Package, f *ssa.Function) (llssa.Function, llssa.PyObjRef, int) {
@@ -246,10 +255,11 @@ func (p *context) compileFuncDecl(pkg llssa.Package, f *ssa.Function) (llssa.Fun
 			fn.Inline(llssa.NoInline)
 		}
 	}
+	isCgo := isCgoCfuncOrCmacro(f)
 	if nblk := len(f.Blocks); nblk > 0 {
 		p.cgoCalled = false
 		p.cgoArgs = nil
-		if isCgoCfunc(f) {
+		if isCgo {
 			fn.MakeBlocks(1)
 		} else {
 			fn.MakeBlocks(nblk) // to set fn.HasBody() = true
@@ -278,7 +288,7 @@ func (p *context) compileFuncDecl(pkg llssa.Package, f *ssa.Function) (llssa.Fun
 			}
 			p.bvals = make(map[ssa.Value]llssa.Expr)
 			off := make([]int, len(f.Blocks))
-			if isCgoCfunc(f) {
+			if isCgo {
 				p.cgoArgs = make([]llssa.Expr, len(f.Params))
 				for i, param := range f.Params {
 					p.cgoArgs[i] = p.compileValue(b, param)
@@ -295,7 +305,7 @@ func (p *context) compileFuncDecl(pkg llssa.Package, f *ssa.Function) (llssa.Fun
 				doMainInit := (i == 0 && name == "main")
 				doModInit := (i == 1 && isInit)
 				p.compileBlock(b, block, off[i], doMainInit, doModInit)
-				if isCgoCfunc(f) {
+				if isCgo {
 					// just process first block for performance
 					break
 				}
@@ -409,36 +419,46 @@ func (p *context) compileBlock(b llssa.Builder, block *ssa.BasicBlock, n int, do
 	if funcs, ok := p.cgoFuncs[fname]; ok {
 		cgoFuncs = funcs
 	}
+	fnName := block.Parent().Name()
 	cgoReturned := false
+	isCgoCfunc := isCgoCfunc(fnName)
+	isCgoCmacro := isCgoCmacro(fnName)
 	for i, instr := range instrs {
 		if i == 1 && doModInit && p.state == pkgInPatch { // in patch package but no pkgFNoOldInit
 			initFnNameOld := initFnNameOfHasPatch(p.fn.Name())
 			fnOld := pkg.NewFunc(initFnNameOld, llssa.NoArgsNoRet, llssa.InC)
 			b.Call(fnOld.Expr)
 		}
-		if isCgoCfunc(block.Parent()) {
+		if isCgoCfunc || isCgoCmacro {
 			switch instr := instr.(type) {
 			case *ssa.Alloc:
 				// return value allocation
 				p.compileInstr(b, instr)
 			case *ssa.UnOp:
 				// load cgo function pointer
-				if instr.Op == token.MUL && strings.HasPrefix(instr.X.Name(), "_cgo_") {
-					cgoFuncs = append(cgoFuncs, instr.X.Name())
+				varName := instr.X.Name()
+				if instr.Op == token.MUL && strings.HasPrefix(varName, "_cgo_") {
+					cgoFuncs = append(cgoFuncs, varName)
 					p.cgoFuncs[fname] = cgoFuncs
 					p.compileInstr(b, instr)
 				}
 			case *ssa.Call:
-				// call c function
-				p.compileInstr(b, instr)
-				p.cgoCalled = true
+				if isCgoCmacro {
+					p.cgoRet = p.compileValue(b, instr.Call.Args[0])
+					p.cgoCalled = true
+				} else {
+					// call c function
+					p.compileInstr(b, instr)
+					p.cgoCalled = true
+				}
 			case *ssa.Return:
 				// return cgo function result
-				if len(instr.Results) > 0 {
-					b.Return(p.cgoRet)
-				} else {
-					b.Return(llssa.Nil)
+				if isCgoCmacro {
+					ty := p.type_(instr.Results[0].Type(), llssa.InGo)
+					p.cgoRet.Type = p.prog.Pointer(ty)
+					p.cgoRet = b.Load(p.cgoRet)
 				}
+				b.Return(p.cgoRet)
 				cgoReturned = true
 			}
 		} else {
@@ -446,18 +466,14 @@ func (p *context) compileBlock(b llssa.Builder, block *ssa.BasicBlock, n int, do
 		}
 	}
 	// is cgo cfunc but not return yet, some funcs has multiple blocks
-	if isCgoCfunc(block.Parent()) && !cgoReturned {
+	if (isCgoCfunc || isCgoCmacro) && !cgoReturned {
 		if !p.cgoCalled {
 			panic("cgo cfunc not called")
 		}
 		for _, block := range block.Parent().Blocks {
 			for _, instr := range block.Instrs {
-				if instr, ok := instr.(*ssa.Return); ok {
-					if len(instr.Results) > 0 {
-						b.Return(p.cgoRet)
-					} else {
-						b.Return(llssa.Nil)
-					}
+				if _, ok := instr.(*ssa.Return); ok {
+					b.Return(p.cgoRet)
 					goto end
 				}
 			}