From: Josh Bleecher Snyder <josharian@gmail.com>
Date: Tue, 11 Aug 2015 21:23:08 +0000 (-0700)
Subject: [dev.ssa] cmd/compile: fix function call memory accounting
X-Git-Tag: go1.7beta1~1623^2^2~288
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=2af06480140dd48a4dc54257c2da46a73ca3ebb5;p=gostls13.git

[dev.ssa] cmd/compile: fix function call memory accounting

We were not recording function calls as
changing the state of memory.

As a result, the scheduler was not aware that
storing values to the stack in order to make a
function call must happen *after* retrieving
results from the stack from a just-completed
function call.

This fixes the container/ring tests.

This was my first experience debugging an issue
using the HTML output. I'm feeling quite
pleased with it.

Change-Id: I9e8276846be9fd7a60422911b11816c5175e3d0a
Reviewed-on: https://go-review.googlesource.com/13560
Reviewed-by: Keith Randall <khr@golang.org>
---

diff --git a/src/cmd/compile/internal/gc/ssa.go b/src/cmd/compile/internal/gc/ssa.go
index 13a6d6c009..dcc7de8d04 100644
--- a/src/cmd/compile/internal/gc/ssa.go
+++ b/src/cmd/compile/internal/gc/ssa.go
@@ -1319,6 +1319,7 @@ func (s *state) expr(n *Node) *ssa.Value {
 
 		// read result from stack at the start of the fallthrough block
 		s.startBlock(bNext)
+		s.vars[&memvar] = call
 		var titer Iter
 		fp := Structfirst(&titer, Getoutarg(left.Type))
 		if fp == nil {