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////////////QUANTUM_SIZE = GUARD_STACK = 1;
// Generates code that can be placed inline in generated code.
// This is not the cleanest way to write this kind of code - it is
// optimized for generating fast inline code.
RuntimeGenerator = {
alloc: function(size, type) {
var ret = type + 'TOP';
// ret += '; for (var i = 0; i < ' + size + '; i++) HEAP[' + type + 'TOP+i] = 0';
if (GUARD_MEMORY) {
ret += '; assert(' + size + ' > 0)';
}
ret += '; ' + type + 'TOP += ' + size;
if (QUANTUM_SIZE > 1) {
ret += ';' + RuntimeGenerator.alignMemory(type + 'TOP', QUANTUM_SIZE);
}
return ret;
},
// An allocation that lives as long as the current function call
stackAlloc: function(size) {
var ret = RuntimeGenerator.alloc(size, 'STACK');
if (GUARD_MEMORY) {
ret += '; assert(STACKTOP < STACK_ROOT + STACK_MAX)';
}
return ret;
},
stackEnter: function(initial) {
if (initial === 0) return ''; // XXX Note that we don't even push the stack! This is faster, but
// means that we don't clear stack allocations done in this function
// until the parent unwinds its stack. So potentially if we are in
// a loop, we can use a lot of memory.
var ret = 'var __stackBase__ = STACKTOP; STACKTOP += ' + initial;
if (GUARD_MEMORY) {
ret += '; assert(STACKTOP < STACK_MAX)';
}
return ret;
},
stackExit: function(initial) {
if (initial === 0) return ''; // XXX See comment in stackEnter
return 'STACKTOP = __stackBase__';
},
// An allocation that cannot be free'd
staticAlloc: function(size) {
return RuntimeGenerator.alloc(size, 'STATIC');
},
alignMemory: function(target, quantum) {
if (typeof quantum !== 'number') {
quantum = '(quantum ? quantum : QUANTUM_SIZE)';
}
return target + ' = Math.ceil(' + target + '/' + quantum + ')*' + quantum + ';';
},
};
function unInline(name_, params) {
var src = '(function ' + name_ + '(' + params + ') { var ret = ' + RuntimeGenerator[name_].apply(null, params) + '; return ret; })';
//print('src: ' + src);
return eval(src);
}
// Uses the RuntimeGenerator during compilation, in order to
// 1. Let the compiler access and run those functions during compilation
// 2. We expose the entire Runtime object to generated code, so it can
// use that functionality in a non-inline manner.
Runtime = {
stackAlloc: unInline('stackAlloc', ['size']),
staticAlloc: unInline('staticAlloc', ['size']),
alignMemory: unInline('alignMemory', ['size', 'quantum']),
};
function getRuntime() {
var ret = '';
for (i in Runtime) {
ret += Runtime[i].toString() + '\n';
}
return ret + '\n';
}
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