[6a3d2e7] | 1 | // |
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| 2 | // Cforall Version 1.0.0 Copyright (C) 2016 University of Waterloo |
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| 3 | // |
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| 4 | // The contents of this file are covered under the licence agreement in the |
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| 5 | // file "LICENCE" distributed with Cforall. |
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| 6 | // |
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[75a17f1] | 7 | // coroutine.c -- |
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[6a3d2e7] | 8 | // |
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| 9 | // Author : Thierry Delisle |
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| 10 | // Created On : Mon Nov 28 12:27:26 2016 |
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[6b0b624] | 11 | // Last Modified By : Peter A. Buhr |
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[f5f2768] | 12 | // Last Modified On : Thu Feb 16 15:34:46 2023 |
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| 13 | // Update Count : 24 |
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[6a3d2e7] | 14 | // |
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| 15 | |
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[2026bb6] | 16 | #define __cforall_thread__ |
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| 17 | |
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[58b6d1b] | 18 | #include "coroutine.hfa" |
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[bd98b58] | 19 | |
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[6a3d2e7] | 20 | #include <stddef.h> |
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| 21 | #include <malloc.h> |
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| 22 | #include <errno.h> |
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| 23 | #include <string.h> |
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| 24 | #include <unistd.h> |
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[ada0246d] | 25 | #include <sys/mman.h> // mprotect |
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[76e069f] | 26 | #include <unwind.h> |
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[6a3d2e7] | 27 | |
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[708ae38] | 28 | #include "kernel/private.hfa" |
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[c960331] | 29 | #include "exception.hfa" |
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[bfcf6b9] | 30 | #include "math.hfa" |
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[6a3d2e7] | 31 | |
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[97229d6] | 32 | #define CFA_COROUTINE_USE_MMAP 0 |
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| 33 | |
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[6a3d2e7] | 34 | #define __CFA_INVOKE_PRIVATE__ |
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| 35 | #include "invoke.h" |
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| 36 | |
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[76e069f] | 37 | extern "C" { |
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[e84ab3d] | 38 | void _CtxCoroutine_Unwind(struct _Unwind_Exception * storage, struct coroutine$ *) __attribute__ ((__noreturn__)); |
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[b2f6113] | 39 | static void _CtxCoroutine_UnwindCleanup(_Unwind_Reason_Code, struct _Unwind_Exception *) __attribute__ ((__noreturn__)); |
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| 40 | static void _CtxCoroutine_UnwindCleanup(_Unwind_Reason_Code, struct _Unwind_Exception *) { |
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| 41 | abort(); |
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| 42 | } |
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[f019069] | 43 | |
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| 44 | extern void CtxRet( struct __stack_context_t * to ) asm ("CtxRet") __attribute__ ((__noreturn__)); |
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[76e069f] | 45 | } |
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| 46 | |
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[1c01c58] | 47 | //----------------------------------------------------------------------------- |
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[fd54fef] | 48 | forall(T &) |
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[c18bf9e] | 49 | void copy(CoroutineCancelled(T) * dst, CoroutineCancelled(T) * src) libcfa_public { |
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[342be43] | 50 | dst->virtual_table = src->virtual_table; |
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[1c01c58] | 51 | dst->the_coroutine = src->the_coroutine; |
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| 52 | dst->the_exception = src->the_exception; |
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| 53 | } |
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| 54 | |
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[fd54fef] | 55 | forall(T &) |
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[c18bf9e] | 56 | const char * msg(CoroutineCancelled(T) *) libcfa_public { |
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[1c01c58] | 57 | return "CoroutineCancelled(...)"; |
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| 58 | } |
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| 59 | |
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| 60 | // This code should not be inlined. It is the error path on resume. |
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[fd54fef] | 61 | forall(T & | is_coroutine(T)) |
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[b583113] | 62 | void __cfaehm_cancelled_coroutine( |
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[c3b9d639] | 63 | T & cor, coroutine$ * desc, EHM_DEFAULT_VTABLE(CoroutineCancelled(T)) ) libcfa_public { |
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[1c01c58] | 64 | verify( desc->cancellation ); |
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| 65 | desc->state = Cancelled; |
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[342be43] | 66 | exception_t * except = __cfaehm_cancellation_exception( desc->cancellation ); |
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[1c01c58] | 67 | |
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[69c5c00] | 68 | // TODO: Remove explitate vtable set once trac#186 is fixed. |
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[b583113] | 69 | CoroutineCancelled(T) except; |
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| 70 | except.virtual_table = &_default_vtable; |
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[1c01c58] | 71 | except.the_coroutine = &cor; |
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| 72 | except.the_exception = except; |
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[ecfd758] | 73 | // Why does this need a cast? |
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[b583113] | 74 | throwResume (CoroutineCancelled(T) &)except; |
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[1c01c58] | 75 | |
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| 76 | except->virtual_table->free( except ); |
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| 77 | free( desc->cancellation ); |
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| 78 | desc->cancellation = 0p; |
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| 79 | } |
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| 80 | |
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[6a3d2e7] | 81 | //----------------------------------------------------------------------------- |
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| 82 | // Global state variables |
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| 83 | |
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| 84 | // minimum feasible stack size in bytes |
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[290553a] | 85 | static const size_t MinStackSize = 1000; |
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[b2f6113] | 86 | extern size_t __page_size; // architecture pagesize HACK, should go in proper runtime singleton |
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[dd92fe9] | 87 | extern int __map_prot; |
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[b2f6113] | 88 | |
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| 89 | void __stack_prepare( __stack_info_t * this, size_t create_size ); |
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[c18bf9e] | 90 | static void __stack_clean ( __stack_info_t * this ); |
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[6a3d2e7] | 91 | |
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| 92 | //----------------------------------------------------------------------------- |
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| 93 | // Coroutine ctors and dtors |
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[b2f6113] | 94 | void ?{}( __stack_info_t & this, void * storage, size_t storageSize ) { |
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| 95 | this.storage = (__stack_t *)storage; |
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| 96 | |
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| 97 | // Did we get a piece of storage ? |
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| 98 | if (this.storage || storageSize != 0) { |
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| 99 | // We either got a piece of storage or the user asked for a specific size |
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| 100 | // Immediately create the stack |
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| 101 | // (This is slightly unintuitive that non-default sized coroutines create are eagerly created |
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| 102 | // but it avoids that all coroutines carry an unnecessary size) |
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| 103 | verify( storageSize != 0 ); |
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| 104 | __stack_prepare( &this, storageSize ); |
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| 105 | } |
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[6a3d2e7] | 106 | } |
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| 107 | |
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[b2f6113] | 108 | void ^?{}(__stack_info_t & this) { |
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[8c01e1b] | 109 | bool userStack = ((intptr_t)this.storage & 0x1) != 0; |
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| 110 | if ( ! userStack && this.storage ) { |
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[bfcf6b9] | 111 | __stack_clean( &this ); |
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[b2f6113] | 112 | } |
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[6a3d2e7] | 113 | } |
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| 114 | |
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[c18bf9e] | 115 | void ?{}( coroutine$ & this, const char name[], void * storage, size_t storageSize ) libcfa_public with( this ) { |
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[524627e] | 116 | (this.context){0p, 0p}; |
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[b2f6113] | 117 | (this.stack){storage, storageSize}; |
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| 118 | this.name = name; |
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| 119 | state = Start; |
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[524627e] | 120 | starter = 0p; |
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| 121 | last = 0p; |
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| 122 | cancellation = 0p; |
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[2fe64ba] | 123 | ehm_state.ehm_buffer{}; |
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| 124 | ehm_state.buffer_lock{}; |
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| 125 | ehm_state.ehm_enabled = false; |
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[6a3d2e7] | 126 | } |
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| 127 | |
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[c18bf9e] | 128 | void ^?{}(coroutine$& this) libcfa_public { |
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[3623f9d] | 129 | if(this.state != Halted && this.state != Start && this.state != Primed) { |
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[e84ab3d] | 130 | coroutine$ * src = active_coroutine(); |
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| 131 | coroutine$ * dst = &this; |
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[b2f6113] | 132 | |
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| 133 | struct _Unwind_Exception storage; |
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| 134 | storage.exception_class = -1; |
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| 135 | storage.exception_cleanup = _CtxCoroutine_UnwindCleanup; |
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| 136 | this.cancellation = &storage; |
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| 137 | this.last = src; |
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| 138 | |
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| 139 | // not resuming self ? |
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| 140 | if ( src == dst ) { |
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| 141 | abort( "Attempt by coroutine %.256s (%p) to terminate itself.\n", src->name, src ); |
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| 142 | } |
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| 143 | |
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[ac2b598] | 144 | $ctx_switch( src, dst ); |
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[b2f6113] | 145 | } |
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[76e069f] | 146 | } |
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[6a3d2e7] | 147 | |
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| 148 | // Part of the Public API |
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| 149 | // Not inline since only ever called once per coroutine |
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[c3b9d639] | 150 | forall(T & | is_coroutine(T) | { EHM_DEFAULT_VTABLE(CoroutineCancelled(T)); }) |
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[c18bf9e] | 151 | void prime(T& cor) libcfa_public { |
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[e84ab3d] | 152 | coroutine$* this = get_coroutine(cor); |
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[b2f6113] | 153 | assert(this->state == Start); |
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[6a3d2e7] | 154 | |
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[b2f6113] | 155 | this->state = Primed; |
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| 156 | resume(cor); |
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[6a3d2e7] | 157 | } |
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| 158 | |
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[c18bf9e] | 159 | static [void *, size_t] __stack_alloc( size_t storageSize ) { |
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[0030ada3] | 160 | const size_t stack_data_size = libCeiling( sizeof(__stack_t), 16 ); // minimum alignment |
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[b2f6113] | 161 | assert(__page_size != 0l); |
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| 162 | size_t size = libCeiling( storageSize, 16 ) + stack_data_size; |
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[bfcf6b9] | 163 | size = ceiling(size, __page_size); |
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[b2f6113] | 164 | |
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| 165 | // If we are running debug, we also need to allocate a guardpage to catch stack overflows. |
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| 166 | void * storage; |
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[97229d6] | 167 | #if CFA_COROUTINE_USE_MMAP |
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| 168 | storage = mmap(0p, size + __page_size, PROT_EXEC | PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, 0, 0); |
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| 169 | if(storage == ((void*)-1)) { |
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| 170 | abort( "coroutine stack creation : internal error, mmap failure, error(%d) %s.", errno, strerror( errno ) ); |
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| 171 | } |
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| 172 | if ( mprotect( storage, __page_size, PROT_NONE ) == -1 ) { |
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| 173 | abort( "coroutine stack creation : internal error, mprotect failure, error(%d) %s.", errno, strerror( errno ) ); |
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| 174 | } // if |
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| 175 | storage = (void *)(((intptr_t)storage) + __page_size); |
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| 176 | #else |
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| 177 | __cfaabi_dbg_debug_do( |
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| 178 | storage = memalign( __page_size, size + __page_size ); |
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| 179 | ); |
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| 180 | __cfaabi_dbg_no_debug_do( |
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| 181 | storage = (void*)malloc(size); |
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| 182 | ); |
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| 183 | |
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| 184 | __cfaabi_dbg_debug_do( |
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| 185 | if ( mprotect( storage, __page_size, PROT_NONE ) == -1 ) { |
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| 186 | abort( "__stack_alloc : internal error, mprotect failure, error(%d) %s.", (int)errno, strerror( (int)errno ) ); |
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| 187 | } |
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| 188 | storage = (void *)(((intptr_t)storage) + __page_size); |
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| 189 | ); |
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| 190 | #endif |
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| 191 | __cfaabi_dbg_print_safe("Kernel : Created stack %p of size %zu\n", storage, size); |
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[b2f6113] | 192 | |
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| 193 | verify( ((intptr_t)storage & (libAlign() - 1)) == 0ul ); |
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| 194 | return [storage, size]; |
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| 195 | } |
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[6a3d2e7] | 196 | |
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[c18bf9e] | 197 | static void __stack_clean ( __stack_info_t * this ) { |
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[bfcf6b9] | 198 | void * storage = this->storage->limit; |
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| 199 | |
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[97229d6] | 200 | #if CFA_COROUTINE_USE_MMAP |
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[85ac70e8] | 201 | size_t size = ((intptr_t)this->storage->base) - ((intptr_t)this->storage->limit) + sizeof(__stack_t); |
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[97229d6] | 202 | storage = (void *)(((intptr_t)storage) - __page_size); |
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| 203 | if(munmap(storage, size + __page_size) == -1) { |
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| 204 | abort( "coroutine stack destruction : internal error, munmap failure, error(%d) %s.", errno, strerror( errno ) ); |
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| 205 | } |
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| 206 | #else |
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| 207 | __cfaabi_dbg_debug_do( |
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| 208 | storage = (char*)(storage) - __page_size; |
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[dd92fe9] | 209 | if ( mprotect( storage, __page_size, __map_prot ) == -1 ) { |
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[97229d6] | 210 | abort( "(coStack_t *)%p.^?{}() : internal error, mprotect failure, error(%d) %s.", &this, errno, strerror( errno ) ); |
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| 211 | } |
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| 212 | ); |
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| 213 | |
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| 214 | free( storage ); |
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| 215 | #endif |
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| 216 | __cfaabi_dbg_print_safe("Kernel : Deleting stack %p\n", storage); |
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[bfcf6b9] | 217 | } |
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| 218 | |
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[c18bf9e] | 219 | void __stack_prepare( __stack_info_t * this, size_t create_size ) libcfa_public { |
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[0030ada3] | 220 | const size_t stack_data_size = libCeiling( sizeof(__stack_t), 16 ); // minimum alignment |
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[b2f6113] | 221 | bool userStack; |
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| 222 | void * storage; |
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| 223 | size_t size; |
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| 224 | if ( !this->storage ) { |
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| 225 | userStack = false; |
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| 226 | [storage, size] = __stack_alloc( create_size ); |
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| 227 | } else { |
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| 228 | userStack = true; |
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[69a61d2] | 229 | __cfaabi_dbg_print_safe("Kernel : stack obj %p using user stack %p(%zd bytes)\n", this, this->storage, (intptr_t)this->storage->limit - (intptr_t)this->storage->base); |
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[b2f6113] | 230 | |
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| 231 | // The stack must be aligned, advance the pointer to the next align data |
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| 232 | storage = (void*)libCeiling( (intptr_t)this->storage, libAlign()); |
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| 233 | |
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| 234 | // The size needs to be shrinked to fit all the extra data structure and be aligned |
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| 235 | ptrdiff_t diff = (intptr_t)storage - (intptr_t)this->storage; |
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| 236 | size = libFloor(create_size - stack_data_size - diff, libAlign()); |
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| 237 | } // if |
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[9b0c3ec5] | 238 | assertf( size >= MinStackSize, "Stack size %zd provides less than minimum of %zd bytes for a stack.", size, MinStackSize ); |
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[b2f6113] | 239 | |
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[bfcf6b9] | 240 | this->storage = (__stack_t *)((intptr_t)storage + size - sizeof(__stack_t)); |
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[b2f6113] | 241 | this->storage->limit = storage; |
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[bfcf6b9] | 242 | this->storage->base = (void*)((intptr_t)storage + size - sizeof(__stack_t)); |
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[1c01c58] | 243 | this->storage->exception_context.top_resume = 0p; |
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| 244 | this->storage->exception_context.current_exception = 0p; |
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[ffe2fad] | 245 | __attribute__((may_alias)) intptr_t * istorage = (intptr_t*)&this->storage; |
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| 246 | *istorage |= userStack ? 0x1 : 0x0; |
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[6a3d2e7] | 247 | } |
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| 248 | |
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[0c92c9f] | 249 | // We need to call suspend from invoke.c, so we expose this wrapper that |
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| 250 | // is not inline (We can't inline Cforall in C) |
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| 251 | extern "C" { |
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[e84ab3d] | 252 | void __cfactx_cor_leave( struct coroutine$ * src ) { |
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| 253 | coroutine$ * starter = src->cancellation != 0 ? src->last : src->starter; |
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[b2f6113] | 254 | |
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| 255 | src->state = Halted; |
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| 256 | |
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| 257 | assertf( starter != 0, |
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| 258 | "Attempt to suspend/leave coroutine \"%.256s\" (%p) that has never been resumed.\n" |
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| 259 | "Possible cause is a suspend executed in a member called by a coroutine user rather than by the coroutine main.", |
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| 260 | src->name, src ); |
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| 261 | assertf( starter->state != Halted, |
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| 262 | "Attempt by coroutine \"%.256s\" (%p) to suspend/leave back to terminated coroutine \"%.256s\" (%p).\n" |
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| 263 | "Possible cause is terminated coroutine's main routine has already returned.", |
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| 264 | src->name, src, starter->name, starter ); |
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| 265 | |
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[ac2b598] | 266 | $ctx_switch( src, starter ); |
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[b2f6113] | 267 | } |
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[09f357ec] | 268 | |
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[e84ab3d] | 269 | struct coroutine$ * __cfactx_cor_finish(void) { |
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| 270 | struct coroutine$ * cor = active_coroutine(); |
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[09f357ec] | 271 | |
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[ab5baab] | 272 | // get the active thread once |
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[e84ab3d] | 273 | thread$ * athrd = active_thread(); |
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[ab5baab] | 274 | |
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| 275 | /* paranoid */ verify( athrd->corctx_flag ); |
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| 276 | athrd->corctx_flag = false; |
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| 277 | |
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[09f357ec] | 278 | if(cor->state == Primed) { |
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[427854b] | 279 | __cfactx_suspend(); |
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[09f357ec] | 280 | } |
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| 281 | |
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| 282 | cor->state = Active; |
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| 283 | |
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| 284 | return cor; |
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| 285 | } |
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[0c92c9f] | 286 | } |
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| 287 | |
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[2fe64ba] | 288 | |
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| 289 | //////////////////////////////////////////////////////////////////////////////////////////////////// |
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| 290 | // non local ehm routines |
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| 291 | |
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| 292 | // helper for popping from coroutine's ehm buffer |
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| 293 | inline nonlocal_exception * pop_ehm_head( coroutine$ * this ) { |
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| 294 | lock( this->ehm_state.buffer_lock __cfaabi_dbg_ctx2 ); |
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| 295 | nonlocal_exception * nl_ex = pop_head( this->ehm_state.ehm_buffer ); |
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| 296 | unlock( this->ehm_state.buffer_lock ); |
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| 297 | return nl_ex; |
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| 298 | } |
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| 299 | |
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| 300 | // user facing ehm operations |
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| 301 | forall(T & | is_coroutine(T)) { |
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| 302 | // enable/disable non-local exceptions |
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| 303 | void enable_ehm( T & cor ) libcfa_public { get_coroutine( cor )->ehm_state.ehm_enabled = true; } |
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| 304 | void disable_ehm( T & cor ) libcfa_public { get_coroutine( cor )->ehm_state.ehm_enabled = false; } |
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| 305 | |
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| 306 | // poll for non-local exceptions |
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| 307 | bool poll( T & cor ) libcfa_public { |
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| 308 | coroutine$ * base_cor = get_coroutine( cor ); |
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| 309 | nonlocal_exception * nl_ex = pop_ehm_head( base_cor ); |
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| 310 | |
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| 311 | // if no exceptions return false |
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| 312 | if ( nl_ex == 0p ) return false; |
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| 313 | |
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| 314 | // otherwise loop and throwResume all pending exceptions |
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| 315 | while ( nl_ex != 0p ){ |
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| 316 | exception_t * ex = nl_ex->the_exception; |
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| 317 | free( nl_ex ); |
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| 318 | throwResume *ex; |
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| 319 | nl_ex = pop_ehm_head( base_cor ); |
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| 320 | } |
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| 321 | |
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| 322 | return true; |
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| 323 | } |
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| 324 | |
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| 325 | // poll iff nonlocal ehm is enabled |
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| 326 | bool checked_poll( T & cor ) libcfa_public { return get_coroutine( cor )->ehm_state.ehm_enabled ? poll( cor ) : false; } |
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[c3e510b] | 327 | |
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| 328 | coroutine$ * resumer( T & cor ) libcfa_public { return get_coroutine( cor )->last; } |
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[2fe64ba] | 329 | } |
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| 330 | |
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| 331 | // resume non local exception at receiver (i.e. enqueue in ehm buffer) |
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| 332 | forall(exceptT &, T & | ehm_resume_at( exceptT, T )) |
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| 333 | void resumeAt( T & receiver, exceptT & ex ) libcfa_public { |
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| 334 | coroutine$ * cor = get_coroutine( receiver ); |
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| 335 | nonlocal_exception * nl_ex = alloc(); |
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| 336 | (*nl_ex){ (exception_t *)&ex }; |
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| 337 | lock( cor->ehm_state.buffer_lock __cfaabi_dbg_ctx2 ); |
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| 338 | append( cor->ehm_state.ehm_buffer, nl_ex ); |
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| 339 | unlock( cor->ehm_state.buffer_lock ); |
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| 340 | } |
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| 341 | |
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[c3e510b] | 342 | forall(exceptT & | { void $throwResume(exceptT &); }) |
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| 343 | void resumeAt( coroutine$ * receiver, exceptT & ex ) libcfa_public { |
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| 344 | nonlocal_exception * nl_ex = alloc(); |
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| 345 | (*nl_ex){ (exception_t *)&ex }; |
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| 346 | lock( receiver->ehm_state.buffer_lock __cfaabi_dbg_ctx2 ); |
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| 347 | append( receiver->ehm_state.ehm_buffer, nl_ex ); |
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| 348 | unlock( receiver->ehm_state.buffer_lock ); |
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| 349 | } |
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| 350 | |
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[6a3d2e7] | 351 | // Local Variables: // |
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| 352 | // mode: c // |
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| 353 | // tab-width: 4 // |
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[4aa2fb2] | 354 | // End: // |
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