cybercyst/go
1
0
Fork 0
mirror of https://github.com/golang/go.git synced 2025-05-05 23:53:05 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

[dev.ssa] cmd/compile: shrink stack guard

Browse Source 
Our stack frame sizes look pretty good now.  Lower the stack
guard from 1024 to 720.
Tip is currently using 720.
We could go lower (to 640 at least) except PPC doesn't like that.

Change-Id: Ie5f96c0e822435638223f1e8a2bd1a1eed68e6aa
Reviewed-on: https://go-review.googlesource.com/19922
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
This commit is contained in:
Keith Randall 2016-02-25 11:40:51 -08:00
parent 378a863682
commit d3f15ff6bc
3 changed files with 4 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
src/cmd/internal/obj/stack.go
View File

@ -11,7 +11,7 @@ const (
STACKSYSTEM = 0 STACKSYSTEM = 0
StackSystem = STACKSYSTEM StackSystem = STACKSYSTEM
StackBig = 4096 StackBig = 4096
StackGuard = 1024*stackGuardMultiplier + StackSystem StackGuard = 720*stackGuardMultiplier + StackSystem
StackSmall = 128 StackSmall = 128
StackLimit = StackGuard - StackSystem - StackSmall StackLimit = StackGuard - StackSystem - StackSmall
) )

2
src/runtime/stack.go
View File

@ -90,7 +90,7 @@ const (
// The stack guard is a pointer this many bytes above the // The stack guard is a pointer this many bytes above the
// bottom of the stack. // bottom of the stack.
_StackGuard = 1024*sys.StackGuardMultiplier + _StackSystem _StackGuard = 720*sys.StackGuardMultiplier + _StackSystem
// After a stack split check the SP is allowed to be this // After a stack split check the SP is allowed to be this
// many bytes below the stack guard. This saves an instruction // many bytes below the stack guard. This saves an instruction

4
test/nosplit.go
View File

@ -302,13 +302,13 @@ TestCases:
// Instead of rewriting the test cases above, adjust // Instead of rewriting the test cases above, adjust
// the first stack frame to use up the extra bytes. // the first stack frame to use up the extra bytes.
if i == 0 { if i == 0 {
size += (1024 - 128) - 128 size += (720 - 128) - 128
// Noopt builds have a larger stackguard. // Noopt builds have a larger stackguard.
// See ../src/cmd/dist/buildruntime.go:stackGuardMultiplier // See ../src/cmd/dist/buildruntime.go:stackGuardMultiplier
// This increase is included in obj.StackGuard // This increase is included in obj.StackGuard
for _, s := range strings.Split(os.Getenv("GO_GCFLAGS"), " ") { for _, s := range strings.Split(os.Getenv("GO_GCFLAGS"), " ") {
if s == "-N" { if s == "-N" {
size += 1024 size += 720
} }
} }
} }