commit 46c9fd03a5ba63880a6caf24505f003b110ebd77
author David Chase <drchase@google.com> Tue Oct 29 15:59:08 2019 -0400
committer David Chase <drchase@google.com> Sun Nov 10 17:12:35 2019 +0000
tree 10d444e2410e131eb887340ab36ad2833903f6a6
parent 40ebcfaa174a0e789cd214236d9edaaa8a8262d3

cmd/compile: enable optimizer logging for bounds checking

Change-Id: Ic1fc271589b7212e7f604ece93cfe34feff909b2
Reviewed-on: https://go-review.googlesource.com/c/go/+/204160
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

src/cmd/compile/internal/logopt/logopt_test.go

diff --git a/src/cmd/compile/internal/logopt/logopt_test.go b/src/cmd/compile/internal/logopt/logopt_test.go
index ef71a78..f2270fc 100644
--- a/src/cmd/compile/internal/logopt/logopt_test.go
+++ b/src/cmd/compile/internal/logopt/logopt_test.go
@@ -20,12 +20,15 @@
 func bar(y *pair) *int {
 	return &y.b
 }
-
+var a []int
 func foo(w, z *pair) *int {
 	if *bar(w) > 0 {
 		return bar(z)
 	}
-	return nil
+	if a[1] > 0 {
+		a = a[:2]
+	}
+	return &a[0]
 }
 `
 
@@ -102,6 +105,7 @@
 		t.Logf("%s", slogged)
 		// below shows proper inlining and nilcheck
 		want(t, slogged, `{"range":{"start":{"line":9,"character":13},"end":{"line":9,"character":13}},"severity":3,"code":"nilcheck","source":"go compiler","message":"","relatedInformation":[{"location":{"uri":"file://tmpdir/file.go","range":{"start":{"line":4,"character":11},"end":{"line":4,"character":11}}},"message":"inlineLoc"}]}`)
+		want(t, slogged, `{"range":{"start":{"line":11,"character":6},"end":{"line":11,"character":6}},"severity":3,"code":"isInBounds","source":"go compiler","message":""}`)
 	})
 }
 

src/cmd/compile/internal/ssa/checkbce.go

diff --git a/src/cmd/compile/internal/ssa/checkbce.go b/src/cmd/compile/internal/ssa/checkbce.go
index ab842b4..6a9ce2b 100644
--- a/src/cmd/compile/internal/ssa/checkbce.go
+++ b/src/cmd/compile/internal/ssa/checkbce.go
@@ -4,19 +4,31 @@
 
 package ssa
 
+import "cmd/compile/internal/logopt"
+
 // checkbce prints all bounds checks that are present in the function.
 // Useful to find regressions. checkbce is only activated when with
 // corresponding debug options, so it's off by default.
 // See test/checkbce.go
 func checkbce(f *Func) {
-	if f.pass.debug <= 0 {
+	if f.pass.debug <= 0 && !logopt.Enabled() {
 		return
 	}
 
 	for _, b := range f.Blocks {
 		for _, v := range b.Values {
 			if v.Op == OpIsInBounds || v.Op == OpIsSliceInBounds {
-				f.Warnl(v.Pos, "Found %v", v.Op)
+				if f.pass.debug > 0 {
+					f.Warnl(v.Pos, "Found %v", v.Op)
+				}
+				if logopt.Enabled() {
+					if v.Op == OpIsInBounds {
+						logopt.LogOpt(v.Pos, "isInBounds", "checkbce", f.Name)
+					}
+					if v.Op == OpIsSliceInBounds {
+						logopt.LogOpt(v.Pos, "isSliceInBounds", "checkbce", f.Name)
+					}
+				}
 			}
 		}
 	}