1 files changed, 121 insertions, 0 deletions
diff --git a/src/runtime/symtabinl_test.go b/src/runtime/symtabinl_test.go
new file mode 100644
index 0000000..df524ae
--- /dev/null
+++ b/src/runtime/symtabinl_test.go
@@ -0,0 +1,121 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"internal/abi"
+	"runtime/internal/sys"
+)
+
+func XTestInlineUnwinder(t TestingT) {
+	if TestenvOptimizationOff() {
+		t.Skip("skipping test with inlining optimizations disabled")
+	}
+
+	pc1 := abi.FuncPCABIInternal(tiuTest)
+	f := findfunc(pc1)
+	if !f.valid() {
+		t.Fatalf("failed to resolve tiuTest at PC %#x", pc1)
+	}
+
+	want := map[string]int{
+		"tiuInlined1:3 tiuTest:10":               0,
+		"tiuInlined1:3 tiuInlined2:6 tiuTest:11": 0,
+		"tiuInlined2:7 tiuTest:11":               0,
+		"tiuTest:12":                             0,
+	}
+	wantStart := map[string]int{
+		"tiuInlined1": 2,
+		"tiuInlined2": 5,
+		"tiuTest":     9,
+	}
+
+	// Iterate over the PCs in tiuTest and walk the inline stack for each.
+	prevStack := "x"
+	for pc := pc1; pc < pc1+1024 && findfunc(pc) == f; pc += sys.PCQuantum {
+		stack := ""
+		u, uf := newInlineUnwinder(f, pc)
+		if file, _ := u.fileLine(uf); file == "?" {
+			// We're probably in the trailing function padding, where findfunc
+			// still returns f but there's no symbolic information. Just keep
+			// going until we definitely hit the end. If we see a "?" in the
+			// middle of unwinding, that's a real problem.
+			//
+			// TODO: If we ever have function end information, use that to make
+			// this robust.
+			continue
+		}
+		for ; uf.valid(); uf = u.next(uf) {
+			file, line := u.fileLine(uf)
+			const wantFile = "symtabinl_test.go"
+			if !hasSuffix(file, wantFile) {
+				t.Errorf("tiuTest+%#x: want file ...%s, got %s", pc-pc1, wantFile, file)
+			}
+
+			sf := u.srcFunc(uf)
+
+			name := sf.name()
+			const namePrefix = "runtime."
+			if hasPrefix(name, namePrefix) {
+				name = name[len(namePrefix):]
+			}
+			if !hasPrefix(name, "tiu") {
+				t.Errorf("tiuTest+%#x: unexpected function %s", pc-pc1, name)
+			}
+
+			start := int(sf.startLine) - tiuStart
+			if start != wantStart[name] {
+				t.Errorf("tiuTest+%#x: want startLine %d, got %d", pc-pc1, wantStart[name], start)
+			}
+			if sf.funcID != abi.FuncIDNormal {
+				t.Errorf("tiuTest+%#x: bad funcID %v", pc-pc1, sf.funcID)
+			}
+
+			if len(stack) > 0 {
+				stack += " "
+			}
+			stack += FmtSprintf("%s:%d", name, line-tiuStart)
+		}
+
+		if stack != prevStack {
+			prevStack = stack
+
+			t.Logf("tiuTest+%#x: %s", pc-pc1, stack)
+
+			if _, ok := want[stack]; ok {
+				want[stack]++
+			}
+		}
+	}
+
+	// Check that we got all the stacks we wanted.
+	for stack, count := range want {
+		if count == 0 {
+			t.Errorf("missing stack %s", stack)
+		}
+	}
+}
+
+func lineNumber() int {
+	_, _, line, _ := Caller(1)
+	return line // return 0 for error
+}
+
+// Below here is the test data for XTestInlineUnwinder
+
+var tiuStart = lineNumber() // +0
+var tiu1, tiu2, tiu3 int    // +1
+func tiuInlined1() { // +2
+	tiu1++ // +3
+} // +4
+func tiuInlined2() { // +5
+	tiuInlined1() // +6
+	tiu2++        // +7
+} // +8
+func tiuTest() { // +9
+	tiuInlined1() // +10
+	tiuInlined2() // +11
+	tiu3++        // +12
+} // +13