GHC.StgToJS.Rts.Rts

Top level driver of the JavaScript Backend RTS. This file is an implementation of the JS RTS for the JS backend written as an EDSL in Haskell. It assumes the existence of pre-generated JS functions, included as js-sources in base. These functions are similarly assumed for non-inline Primops, See Prim. Most of the elements in this module are constants in Haskell Land which define pieces of the JS RTS.

Documentation

garbageCollector :: JStat

The garbageCollector resets registers and result variables.

resetRegister :: StgReg -> JStat

Reset the register r in JS Land. Note that this "resets" by setting the register to a dummy variable called "null", not by setting to JS's nil value.

resetResultVar :: StgRet -> JStat

Reset the return variable r in JS Land. Note that this "resets" by setting the register to a dummy variable called "null", not by setting to JS's nil value.

closureConstructors :: StgToJSConfig -> JStat

Define closures based on size, these functions are syntactic sugar, e.g., a Haskell function which generates some useful JS. Each Closure constructor follows the naming convention h$cN, where N is a natural number. For example, h$c (with the nat omitted) is a JS Land Constructor for a closure in JS land which has a single entry function f, and no fields; identical to h$c0. h$c1 is a JS Land Constructor for a closure with an entry function f, and a single field x1, 'Just foo' is an example of this kind of closure. h$c2 is a JS Land Constructor for a closure with an entry function and two data fields: x1 and x2. And so on. Note that this has JIT performance implications; you should use h$c1, h$c2, h$c3, ... h$c24 instead of making objects manually so layouts and fields can be changed more easily and so the JIT can optimize better.

stackManip :: JStat

JS Payload to perform stack manipulation in the RTS

bitsIdx :: Integer -> [Int]

bhLneStats :: StgToJSConfig -> JExpr -> JExpr -> JStat

declRegs :: JStat

JS payload to declare the registers

regGettersSetters :: JStat

JS payload to define getters and setters on the registers.

loadRegs :: JStat

JS payload that defines the functions to load each register

assignRegs :: StgToJSConfig -> [JExpr] -> JStat

Assign registers R1 ... Rn in descending order, that is assign Rn first. This function uses the assignRegs' array to construct functions which set the registers.

assignRegs' :: Array Int Ident

JS payload which defines an array of function symbols that set N registers from M parameters. For example, h$l2 compiles to: function h$l4(x1, x2, x3, x4) { h$r4 = x1; h$r3 = x2; h$r2 = x3; h$r1 = x4; };

declRets :: JStat

JS payload to declare return variables.

closureTypes :: JStat

JS payload defining the types closures.

rtsDecls :: JStat

JS payload declaring the RTS functions.

rtsText :: StgToJSConfig -> String

print the embedded RTS to a String

rtsDeclsText :: String

print the RTS declarations to a String.

rts :: StgToJSConfig -> JStat

Wrapper over the RTS to guarentee saturation, see Transform

rts' :: StgToJSConfig -> JStat

JS Payload which defines the embedded RTS.