irgen, driver: modify Compiler.Compile to take a FileSet and Files

This change allows clients to generate IR using "files" received from locations
other than the file system. The regular file parser is moved to a new library,
"driver", which is intended to eventually contain much of the logic from
the existing driver.

Differential Revision: http://reviews.llvm.org/D6794

llvm-svn: 225026

1 files changed, 43 insertions, 0 deletions

diff --git a/llgo/driver/parser.go b/llgo/driver/parser.go
new file mode 100644
index 00000000000..07600f41d44
--- /dev/null
+++ b/llgo/driver/parser.go
@@ -0,0 +1,43 @@
+//===- parser.go - parser wrapper -----------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains functions for calling the parser in an appropriate way for
+// llgo.
+//
+//===----------------------------------------------------------------------===//
+
+package driver
+
+import (
+	"fmt"
+	"go/ast"
+	"go/parser"
+	"go/scanner"
+	"go/token"
+)
+
+func parseFile(fset *token.FileSet, filename string) (*ast.File, error) {
+	// Retain comments; this is important for annotation processing.
+	mode := parser.DeclarationErrors | parser.ParseComments
+	return parser.ParseFile(fset, filename, nil, mode)
+}
+
+func ParseFiles(fset *token.FileSet, filenames []string) ([]*ast.File, error) {
+	files := make([]*ast.File, len(filenames))
+	for i, filename := range filenames {
+		file, err := parseFile(fset, filename)
+		if _, ok := err.(scanner.ErrorList); ok {
+			return nil, err
+		} else if err != nil {
+			return nil, fmt.Errorf("%q: %v", filename, err)
+		}
+		files[i] = file
+	}
+	return files, nil
+}