Completing GCC Go escape analysis in GSoC 2014
Hi, I'm a student interested in working on GCC and want to make a
proposal of GSoC 2014 on GCC Go escape analysis.
I 've read code under /gcc/testsuit/go.* the some source code of
gofrontend, and realization of escape analysis and furthermore
optimization is needed.
Right now I have come up with a small patch of escape test at the
beginning. My patch aims at test for whether escape analysis is
working. Then I want to start some small part of performance function
and write more tests for optimization. Am i on the right direction?
Thanks a lot if anyone can give me some advice.
Ray Li
package main
import(
)
var glob_var = 0
//escape;
func global1(p bool) {
if p == true {
glob_var = 987654321
}
}
//tests for escape as return
//variable v returned as the result of the current function
func escape1() int {
v := 123
return v
}
func escape1b() (int, int) {
x, y := 123, 456
return x, y//both p and q escaped
}
func escape2(p *int) int {
return *p
}
func escape2a(p, q *int) (*int, *int) {
return p, q//escaped
}
func escape2b(p, q *int) (*int, *int) {
return escape2a(p, q) //escaped
}
func escape3(p *int) *int {
q := p
if *p > 0 {
return q //p escaped
} else {
return nil
}
}
//tests for no escape
func noesc1(ptr *int) int {
return *ptr//not escape
}
func noesc2() {
var p int
q := noesc1(&p) //not escape
t := q
_ = t
}
func noesc3() {
var p int
q := escape2(&p) //not escape
_ = q
}
func noesc4() {
var p int
q := escape2(&p) //escape
glob_var = q
}
type T struct {
a, b int
}
func (t *T) foo(x int) (*T, bool) {
t.a = x
t.b = t.a + x
return t, true //escape as return
}
func f() *T {
p, _ := new(T).foo(123)
return p
}
//escape recursively
func escrecursive(p, q int) int {
if p + q > 0 {
return escrecursive(p-1, q-1)
} else {
return p * q //escape as return and also this function become recursively escape
}
}
func main() {
}
Re: Completing GCC Go escape analysis in GSoC 2014
Hi Ian I have spend these 3 days to read lots of documents about Go and gccgo. And scan many papers about escape analysis. I plan to use about next 2 days to read more source code of gccgo. In order to dig more and come to a more detailed and efficient proposal. I need your suggestion: -Which codes must I read firstly, and which are the most important to read very carefully? -Do you have suggestions on where should I start? What small implementations can I firstly accomplish? -What would be the background knowledge needed? As there would be more requirements regarding this specific idea not now obvious. -Are there some documentations or papers should I read now? I really appreciate your help =D Ray On Fri, Mar 14, 2014 at 6:11 AM, Ian Lance Taylor wrote: > On Wed, Mar 12, 2014 at 8:31 PM, Ray Li wrote: >> >> Hi, I'm a student interested in working on GCC and want to make a >> proposal of GSoC 2014 on GCC Go escape analysis. >> >> I 've read code under /gcc/testsuit/go.* the some source code of >> gofrontend, and realization of escape analysis and furthermore >> optimization is needed. >> >> Right now I have come up with a small patch of escape test at the >> beginning. My patch aims at test for whether escape analysis is >> working. Then I want to start some small part of performance function >> and write more tests for optimization. Am i on the right direction? >> Thanks a lot if anyone can give me some advice. > > Thanks for your interest. Yes, all of your examples look correct to > me. > > There is a larger escape analysis test in libgo/go/fmt/fmt_test.go. > That file is copied from the master repository, but in mallocTest the > numbers are changed. Instead of 7 5's and a 20, it should be 0, 1, 1, > 2, 1, 2, 0, 1. > > Ian
[GSoC 2014]Is this proposal suitable?
I have made a proposal and wonder if it is clearly and realistic? Thanks for every correction. Ray GCC Go escape analysis The Project The Project aims to accomplish escape analysis for gccgo. Goal: escape analysis (optimization) converting heap allocation to stack allocation Schedule: 21 April - 25 May Preparation:communicate with mentor, read gccgo source code, get familiar with tools, coding and documenting style, try submit some small patches. 26 May - 8 June Coding to implement escape analysis. 9 June - 15 June Do some tests and improvements. 16 June - 29 June Do optimization work.(converting heap allocation to stack allocation) 30 June - 11 August (if permits)More optimization implementation. Detailed Testing.
Re: [GSoC 2014]Is this proposal suitable?
Thank you. I will made it a little more specific. And now I've made it a little bit slower ... And divide my first stage work into 2 parts for the present. I'll look for more information to accomplish it. On Mon, Mar 17, 2014 at 3:26 AM, Joel Sherrill wrote: > > On Mar 16, 2014 2:15 PM, Ray Li wrote: >> >> I have made a proposal and wonder if it is clearly and realistic? > > I am not a GCC mentor but have mentored for another project for 8 years. I > would like to see more detail. For example, what exactly will you deliver by > midterm? At the end? > > Break the effort into smaller steps so progress is easier to see and > measure. > > A Go developer would have to answer this but I like to see something that > shows a student is in a good place to start. Can you build GCC and Go and > publish test results? Can you provide a small test case showing what is > missing (assuming this is possible)? > > Will you need to do any copyright assignment paperwork? Ian will have to > answer this. > > Break the project down, show you will hit the ground running, and show us > how to measure your progress. > > --joel > RTEMS and GCC > >> >> Thanks for every correction. >> >> Ray GCC Go escape analysis The Project The Project aims to accomplish escape analysis for gccgo. Goal: escape analysis (optimization) converting heap allocation to stack allocation Schedule: 21 April - 25 May Preparation:communicate with mentor, read gccgo source code, get familiar with tools, coding and documenting style, try submit some small patches. 26 May - 8 June Coding to implement GlobalEscape analysis. 9 June - 22 June Coding to implement ArgEscape analysis 23 June - 29 June finish mid-term evaluations Do some tests and improvements. 30 June - 13 July Some implementation work.(optimization: convert heap allocation to stack allocation) 14 July - 11 August (if permits)More optimization implementation. Detailed Testing. Details: Mid-term: The basis implementation of escape analysis.(enable to determine the 3 status of escape (GlobalEscape, ArgEscape and NoEscape)) Final results: Use escape analysis to do optimizations.(I have list one, but I will try as fast to do more...)
