ir: move adding packages from the compiler

compiler/compiler.go

@@ -177,50 +177,8 @@ func (c *Compiler) Parse(mainPath string) error {
 
 	c.ir = ir.NewProgram(lprogram, mainPath)
 
-	// Make a list of packages in import order.
+	// Run some DCE and analysis passes. The results are later used by the
-	packageList := []*ssa.Package{}
+	// compiler.
-	packageSet := map[string]struct{}{}
-	worklist := []string{"runtime", mainPath}
-	for len(worklist) != 0 {
-		pkgPath := worklist[0]
-		pkg := c.ir.Program.ImportedPackage(pkgPath)
-		if pkg == nil {
-			// Non-SSA package (e.g. cgo).
-			packageSet[pkgPath] = struct{}{}
-			worklist = worklist[1:]
-			continue
-		}
-		if _, ok := packageSet[pkgPath]; ok {
-			// Package already in the final package list.
-			worklist = worklist[1:]
-			continue
-		}
-
-		unsatisfiedImports := make([]string, 0)
-		imports := pkg.Pkg.Imports()
-		for _, pkg := range imports {
-			if _, ok := packageSet[pkg.Path()]; ok {
-				continue
-			}
-			unsatisfiedImports = append(unsatisfiedImports, pkg.Path())
-		}
-		if len(unsatisfiedImports) == 0 {
-			// All dependencies of this package are satisfied, so add this
-			// package to the list.
-			packageList = append(packageList, pkg)
-			packageSet[pkgPath] = struct{}{}
-			worklist = worklist[1:]
-		} else {
-			// Prepend all dependencies to the worklist and reconsider this
-			// package (by not removing it from the worklist). At that point, it
-			// must be possible to add it to packageList.
-			worklist = append(unsatisfiedImports, worklist...)
-		}
-	}
-
-	for _, pkg := range packageList {
-		c.ir.AddPackage(pkg)
-	}
 	c.ir.SimpleDCE()                   // remove most dead code
 	c.ir.AnalyseCallgraph()            // set up callgraph
 	c.ir.AnalyseInterfaceConversions() // determine which types are converted to an interface

ir/ir.go

@@ -109,7 +109,48 @@ func NewProgram(lprogram *loader.Program, mainPath string) *Program {
 	program := ssautil.CreateProgram(lprogram, ssa.SanityCheckFunctions|ssa.BareInits|ssa.GlobalDebug)
 	program.Build()
 
-	return &Program{
+	// Make a list of packages in import order.
+	packageList := []*ssa.Package{}
+	packageSet := map[string]struct{}{}
+	worklist := []string{"runtime", mainPath}
+	for len(worklist) != 0 {
+		pkgPath := worklist[0]
+		pkg := program.ImportedPackage(pkgPath)
+		if pkg == nil {
+			// Non-SSA package (e.g. cgo).
+			packageSet[pkgPath] = struct{}{}
+			worklist = worklist[1:]
+			continue
+		}
+		if _, ok := packageSet[pkgPath]; ok {
+			// Package already in the final package list.
+			worklist = worklist[1:]
+			continue
+		}
+
+		unsatisfiedImports := make([]string, 0)
+		imports := pkg.Pkg.Imports()
+		for _, pkg := range imports {
+			if _, ok := packageSet[pkg.Path()]; ok {
+				continue
+			}
+			unsatisfiedImports = append(unsatisfiedImports, pkg.Path())
+		}
+		if len(unsatisfiedImports) == 0 {
+			// All dependencies of this package are satisfied, so add this
+			// package to the list.
+			packageList = append(packageList, pkg)
+			packageSet[pkgPath] = struct{}{}
+			worklist = worklist[1:]
+		} else {
+			// Prepend all dependencies to the worklist and reconsider this
+			// package (by not removing it from the worklist). At that point, it
+			// must be possible to add it to packageList.
+			worklist = append(unsatisfiedImports, worklist...)
+		}
+	}
+
+	p := &Program{
 		Program:              program,
 		mainPkg:              program.ImportedPackage(mainPath),
 		functionMap:          make(map[*ssa.Function]*Function),
@@ -118,6 +159,12 @@ func NewProgram(lprogram *loader.Program, mainPath string) *Program {
 		interfaces:           make(map[string]*Interface),
 		comments:             comments,
 	}
+
+	for _, pkg := range packageList {
+		p.AddPackage(pkg)
+	}
+
+	return p
 }
 
 // Add a package to this Program. All packages need to be added first before any