delphi 堆和栈(国外英文资料).doc

delphi 堆和栈(国外英文资料) Delphi heap and stack [transfer] 2.1 stack The stack is by the operating system when a thread is created, the system automatically created by the top stack is like distribution of the DELPHI in the default stack size is 1M, this can be done by Project-Options-Linker-Max Stack size to change its size. A stack is a thread to execute code where the operating system to load the executable code according to the system scheduling algorithm, in addition also stack storage function parameters and local variables. Stack access is based on 4 byte offset, not according to the needs of dynamic growth, it will be reported beyond the scope of stack overflow. 2.2 pile We have to allocate memory on the stack outside the call to allocate memory on the heap, heap allocation is released by the programmer. The DELPHI is used in GetMem.inc code to manage the heap, the heap contains many uncertain block size. The initial state, only a pile of blocks, i.e. the heap itself. After a period of time for the taking and recovery after the reactor will probably only some cut residual fragments, and these fragments may have been unable to merge. At this time, if a new request is greater than any one fragment, then it must re apply for a new, large block in the stack. The use of heap is always a process of rob Peter to pay Paul. The heap size is 2G, 3G can be achieved in the extended memory mode. Pay attention to it and the data structure in the heap is different, it is similar to the distribution list, when access to stack content need to find the heap, and then traversing the list, so the pile than stack slow access. 2.3 what on the stack 2.3.1 gets the stack and address Get normally the stack address When writing the assembly, we know that the ESP storage stack pointer, EBP storage stack pointer Procedure GetStackAddress (VaR AStackTop, AStackBottom: Cardinal); Begin ASM Mov [eax], ESP; / / the top of the stack, eax receives the first parameter Mov [edx], EBP; / / EDX stack,