cmd/go: support multiple main packages with -pgo=auto

In -pgo=auto mode, the go command finds a profile named
default.pgo in the main package's directly, and if found, use it
as the profile for the build. Currently we only support a single
main package when -pgo=auto is used.

When multiple main packages are included in a build, they may
have different default profiles (or some have profiles whereas
some don't), so a common dependent package would need to be built
multiple times, with different profiles (or lack of). This CL
handles this. To do so, we need to split (unshare) the dependency
graph so they can attach different profiles.

Fixes #58099.

Change-Id: I1ad21361967aafbf5089d8d5e89229f95fe31276
Reviewed-on: https://go-review.googlesource.com/c/go/+/472358
Reviewed-by: Michael Pratt <mpratt@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Cherry Mui <cherryyz@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>

0 files changed, 0 insertions, 0 deletions