cmd/compile/internal/base: enable stack slot merging by default

Flag flip to enable stack slot merging by default when optimizing.
Please see the earlier CL for details on what this is doing.

Updates #62737.
Updates #65532.
Updates #65495.

Change-Id: I8e30d553e74ace43d418f883199721f05320d3d7
Reviewed-on: https://go-review.googlesource.com/c/go/+/576681
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>

diff --git a/src/cmd/compile/internal/base/flag.go b/src/cmd/compile/internal/base/flag.go
index 0889c37b0d40b93036627015b4da9d67bfdf9c8b..1ee3337088b9288d00b29f1801b6ec9e0f4e8d5c 100644 (file)
--- a/src/cmd/compile/internal/base/flag.go
+++ b/src/cmd/compile/internal/base/flag.go
@@ -184,6 +184,7 @@ func ParseFlags() {
        Debug.SyncFrames = -1 // disable sync markers by default
        Debug.ZeroCopy = 1
        Debug.RangeFuncCheck = 1
+       Debug.MergeLocals = 1
 
        Debug.Checkptr = -1 // so we can tell whether it is set explicitly