1
0
mirror of https://github.com/golang/go synced 2024-11-19 17:44:43 -07:00
The Go programming language
Go to file
David Chase d58d90152b cmd/compile: adjust locationlist lifetimes
A statement like

  foo = bar + qux

might compile to

  AX := AX + BX

resulting in a regkill for AX before this instruction.
The buggy behavior is to kill AX "at" this instruction,
before it has executed.  (Code generation of no-instruction
values like RegKills applies their effects at the
next actual instruction emitted).

However, bar is still associated with AX until after the
instruction executes, so the effect of the regkill must
occur at the boundary between this instruction and the
next.  Similarly, the new value bound to AX is not visible
until this instruction executes (and in the case of values
that require multiple instructions in code generation, until
all of them have executed).

The ranges are adjusted so that a value's start occurs
at the next following instruction after its evaluation,
and the end occurs after (execution of) the first
instruction following the end of the lifetime as a value.

(Notice the asymmetry; the entire value must be finished
before it is visible, but execution of a single instruction
invalidates.  However, the value *is* visible before that
next instruction executes).

The test was adjusted to make it insensitive to the result
numbering for variables printed by gdb, since that is not
relevant to the test and makes the differences introduced
by small changes larger than necessary/useful.

The test was also improved to present variable probes
more intuitively, and also to allow explicit indication
of "this variable was optimized out"

Change-Id: I39453eead8399e6bb05ebd957289b112d1100c0e
Reviewed-on: https://go-review.googlesource.com/74090
Run-TryBot: David Chase <drchase@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2017-11-05 18:32:53 +00:00
.github .github: update ISSUE_TEMPLATE to be closer to 'go bug' 2017-08-19 04:06:10 +00:00
api api: update next.txt 2017-10-28 00:00:56 +00:00
doc spec: match syntax for method expressions with implementations 2017-10-25 22:49:03 +00:00
lib/time time: vendor tzdata-2017b and update test 2017-06-07 21:23:58 +00:00
misc all: change github.com issue links to golang.org 2017-11-04 04:13:41 +00:00
src cmd/compile: adjust locationlist lifetimes 2017-11-05 18:32:53 +00:00
test cmd/compile: inline closures with captures 2017-11-05 04:18:05 +00:00
.gitattributes
.gitignore .gitignore: ignore src/cmd/dist/dist 2017-10-28 21:55:49 +00:00
AUTHORS A+C: final updates for Go 1.9 2017-07-18 01:47:54 +00:00
CONTRIBUTING.md .github: recommend 'go bug' when filing an issue 2017-07-24 17:18:34 +00:00
CONTRIBUTORS A+C: final updates for Go 1.9 2017-07-18 01:47:54 +00:00
favicon.ico website: recreate 16px and 32px favicon 2016-08-25 15:43:32 +00:00
LICENSE
PATENTS
README.md readme: add attribution for the Gopher image 2017-02-03 19:39:41 +00:00
robots.txt

The Go Programming Language

Go is an open source programming language that makes it easy to build simple, reliable, and efficient software.

Gopher image Gopher image by Renee French, licensed under Creative Commons 3.0 Attributions license.

Our canonical Git repository is located at https://go.googlesource.com/go. There is a mirror of the repository at https://github.com/golang/go.

Unless otherwise noted, the Go source files are distributed under the BSD-style license found in the LICENSE file.

Download and Install

Binary Distributions

Official binary distributions are available at https://golang.org/dl/.

After downloading a binary release, visit https://golang.org/doc/install or load doc/install.html in your web browser for installation instructions.

Install From Source

If a binary distribution is not available for your combination of operating system and architecture, visit https://golang.org/doc/install/source or load doc/install-source.html in your web browser for source installation instructions.

Contributing

Go is the work of hundreds of contributors. We appreciate your help!

To contribute, please read the contribution guidelines: https://golang.org/doc/contribute.html

Note that the Go project does not use GitHub pull requests, and that we use the issue tracker for bug reports and proposals only. See https://golang.org/wiki/Questions for a list of places to ask questions about the Go language.