github.com/m10x/go/src@v0.0.0-20220112094212-ba61592315da/runtime/internal/sys/consts.go (about)

     1  // Copyright 2014 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package sys
     6  
     7  import (
     8  	"internal/goarch"
     9  	"internal/goos"
    10  )
    11  
    12  // AIX requires a larger stack for syscalls.
    13  const StackGuardMultiplier = StackGuardMultiplierDefault*(1-goos.IsAix) + 2*goos.IsAix
    14  
    15  // DefaultPhysPageSize is the default physical page size.
    16  const DefaultPhysPageSize = goarch.DefaultPhysPageSize
    17  
    18  // PCQuantum is the minimal unit for a program counter (1 on x86, 4 on most other systems).
    19  // The various PC tables record PC deltas pre-divided by PCQuantum.
    20  const PCQuantum = goarch.PCQuantum
    21  
    22  // Int64Align is the required alignment for a 64-bit integer (4 on 32-bit systems, 8 on 64-bit).
    23  const Int64Align = goarch.PtrSize
    24  
    25  // MinFrameSize is the size of the system-reserved words at the bottom
    26  // of a frame (just above the architectural stack pointer).
    27  // It is zero on x86 and PtrSize on most non-x86 (LR-based) systems.
    28  // On PowerPC it is larger, to cover three more reserved words:
    29  // the compiler word, the link editor word, and the TOC save word.
    30  const MinFrameSize = goarch.MinFrameSize
    31  
    32  // StackAlign is the required alignment of the SP register.
    33  // The stack must be at least word aligned, but some architectures require more.
    34  const StackAlign = goarch.StackAlign