blob: 8e3327ee48ff67351a0abba85f5b103ef896562c (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
|
// Copyright 2023 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package abi
const (
// StackNosplitBase is the base maximum number of bytes that a chain of
// NOSPLIT functions can use.
//
// This value must be multiplied by the stack guard multiplier, so do not
// use it directly. See runtime/stack.go:stackNosplit and
// cmd/internal/objabi/stack.go:StackNosplit.
StackNosplitBase = 800
// We have three different sequences for stack bounds checks, depending on
// whether the stack frame of a function is small, big, or huge.
// After a stack split check the SP is allowed to be StackSmall bytes below
// the stack guard.
//
// Functions that need frames <= StackSmall can perform the stack check
// using a single comparison directly between the stack guard and the SP
// because we ensure that StackSmall bytes of stack space are available
// beyond the stack guard.
StackSmall = 128
// Functions that need frames <= StackBig can assume that neither
// SP-framesize nor stackGuard-StackSmall will underflow, and thus use a
// more efficient check. In order to ensure this, StackBig must be <= the
// size of the unmapped space at zero.
StackBig = 4096
)
|
