mirror of git://gcc.gnu.org/git/gcc.git
				
				
				
			
		
			
				
	
	
		
			97 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			97 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
/* go-make-slice.c -- make a slice.
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   Copyright 2011 The Go Authors. All rights reserved.
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   Use of this source code is governed by a BSD-style
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   license that can be found in the LICENSE file.  */
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#include <stdint.h>
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#include "runtime.h"
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#include "go-alloc.h"
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#include "go-assert.h"
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#include "go-panic.h"
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#include "go-type.h"
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#include "array.h"
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#include "arch.h"
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#include "malloc.h"
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/* Dummy word to use as base pointer for make([]T, 0).
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   Since you cannot take the address of such a slice,
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   you can't tell that they all have the same base pointer.  */
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uintptr runtime_zerobase;
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struct __go_open_array
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__go_make_slice2 (const struct __go_type_descriptor *td, uintptr_t len,
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		  uintptr_t cap)
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{
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  const struct __go_slice_type* std;
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  intgo ilen;
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  intgo icap;
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  uintptr_t size;
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  struct __go_open_array ret;
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  __go_assert (td->__code == GO_SLICE);
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  std = (const struct __go_slice_type *) td;
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  ilen = (intgo) len;
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  if (ilen < 0 || (uintptr_t) ilen != len)
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    runtime_panicstring ("makeslice: len out of range");
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  icap = (intgo) cap;
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  if (cap < len
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      || (uintptr_t) icap != cap
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      || (std->__element_type->__size > 0
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	  && cap > MaxMem / std->__element_type->__size))
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    runtime_panicstring ("makeslice: cap out of range");
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  ret.__count = ilen;
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  ret.__capacity = icap;
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  size = cap * std->__element_type->__size;
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  if (size == 0)
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    ret.__values = &runtime_zerobase;
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  else if ((std->__element_type->__code & GO_NO_POINTERS) != 0)
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    ret.__values = runtime_mallocgc (size, FlagNoPointers, 1, 1);
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  else
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    {
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      ret.__values = runtime_mallocgc (size, 0, 1, 1);
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      if (UseSpanType)
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	runtime_settype (ret.__values,
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			 (uintptr) std->__element_type | TypeInfo_Array);
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    }
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  return ret;
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}
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struct __go_open_array
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__go_make_slice1 (const struct __go_type_descriptor *td, uintptr_t len)
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{
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  return __go_make_slice2 (td, len, len);
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}
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struct __go_open_array
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__go_make_slice2_big (const struct __go_type_descriptor *td, uint64_t len,
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		      uint64_t cap)
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{
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  uintptr_t slen;
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  uintptr_t scap;
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  slen = (uintptr_t) len;
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  if ((uint64_t) slen != len)
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    runtime_panicstring ("makeslice: len out of range");
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  scap = (uintptr_t) cap;
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  if ((uint64_t) scap != cap)
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    runtime_panicstring ("makeslice: cap out of range");
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  return __go_make_slice2 (td, slen, scap);
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}
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struct __go_open_array
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__go_make_slice1_big (const struct __go_type_descriptor *td, uint64_t len)
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{
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  return __go_make_slice2_big (td, len, len);
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}
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