Text file src/runtime/asm_ppc64x.h

     1	// Copyright 2015 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	// FIXED_FRAME defines the size of the fixed part of a stack frame. A stack
     6	// frame looks like this:
     7	//
     8	// +---------------------+
     9	// | local variable area |
    10	// +---------------------+
    11	// | argument area       |
    12	// +---------------------+ <- R1+FIXED_FRAME
    13	// | fixed area          |
    14	// +---------------------+ <- R1
    15	//
    16	// So a function that sets up a stack frame at all uses as least FIXED_FRAME
    17	// bytes of stack. This mostly affects assembly that calls other functions
    18	// with arguments (the arguments should be stored at FIXED_FRAME+0(R1),
    19	// FIXED_FRAME+8(R1) etc) and some other low-level places.
    20	//
    21	// The reason for using a constant is to make supporting PIC easier (although
    22	// we only support PIC on ppc64le which has a minimum 32 bytes of stack frame,
    23	// and currently always use that much, PIC on ppc64 would need to use 48).
    24	
    25	#define FIXED_FRAME 32

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