pkg/cover: support compiler frontend coverage

Currently we only support compiler middle/backenend coverage
where we can map coverage points to source line.
Support better frontend coverage where coverage points map
to source code ranges start line:col - end line:col.

2 files changed, 24 insertions, 5 deletions

diff --git a/pkg/cover/backend/backend.go b/pkg/cover/backend/backend.go
index 6df629d74..13ae3b400 100644
--- a/pkg/cover/backend/backend.go
+++ b/pkg/cover/backend/backend.go
@@ -6,7 +6,6 @@ package backend
 import (
 	"fmt"
 
-	"github.com/google/syzkaller/pkg/symbolizer"
 	"github.com/google/syzkaller/sys/targets"
 )
 
@@ -34,10 +33,21 @@ type Symbol struct {
 }
 
 type Frame struct {
-	symbolizer.Frame
+	PC   uint64
+	Name string
 	Path string
+	Range
+}
+
+type Range struct {
+	StartLine int
+	StartCol  int
+	EndLine   int
+	EndCol    int
 }
 
+const LineEnd = 1 << 30
+
 func Make(target *targets.Target, vm, objDir, srcDir, buildDir string) (*Impl, error) {
 	if objDir == "" {
 		return nil, fmt.Errorf("kernel obj directory is not specified")
diff --git a/pkg/cover/backend/elf.go b/pkg/cover/backend/elf.go
index 848422c76..12231c2d0 100644
--- a/pkg/cover/backend/elf.go
+++ b/pkg/cover/backend/elf.go
@@ -293,9 +293,18 @@ func symbolize(target *targets.Target, objDir, srcDir, buildDir, obj string, pcs
 			err0 = res.err
 		}
 		for _, frame := range res.frames {
-			wrap := Frame{frame, ""}
-			wrap.File, wrap.Path = cleanPath(frame.File, objDir, srcDir, buildDir)
-			frames = append(frames, wrap)
+			name, path := cleanPath(frame.File, objDir, srcDir, buildDir)
+			frames = append(frames, Frame{
+				PC:   frame.PC,
+				Name: name,
+				Path: path,
+				Range: Range{
+					StartLine: frame.Line,
+					StartCol:  0,
+					EndLine:   frame.Line,
+					EndCol:    LineEnd,
+				},
+			})
 		}
 	}
 	if err0 != nil {