Changes between Version 70 and Version 71 of Commentary/Compiler/StackAreas


Ignore:
Timestamp:
Sep 19, 2013 2:23:48 PM (23 months ago)
Author:
simonpj
Comment:

--

Legend:

Unmodified
Added
Removed
Modified
  • Commentary/Compiler/StackAreas

    v70 v71  
    5858}}}
    5959
    60 An `Area` represents space on the stack; it may use either the `RegSlot` constructor to represent a single stack slot for a register or the `CallArea` constructor to represent parameters passed to/from a function call/return. In a young `CallArea`, the `BlockId` is the label of the function call's continuation, and it passes parameters to the call. Each `Area` grows down, with offset 0 pointing to the old end of the `Area`. The old call area is the initial state of the stack on entry to the function (the overflow parameters and the return address) as well as any arguments that will be passed to a tail call. Note that `RegSlot` areas are very small (since they only need to store a single register), while `CallArea` are contiguous chunks of arguments.
     60An `Area` represents space on the stack; it may use either the `RegSlot` constructor to represent a single stack slot for a register or the `CallArea` constructor to represent parameters passed to/from a function call/return. In a young `CallArea`, the `BlockId` is the label of the function call's continuation, and it passes parameters to the call.
     61
     62'''Each `Area` grows down, with offset 0 pointing to the old end of the `Area`.'''
     63
     64 The old call area is the initial state of the stack on entry to the function (the overflow parameters and the return address) as well as any arguments that will be passed to a tail call. Note that `RegSlot` areas are very small (since they only need to store a single register), while `CallArea` are contiguous chunks of arguments.
    6165
    6266To name a specific location on the stack, we represent its address with a new kind of `CmmExpr`: the `CmmStackSlot`.