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-rw-r--r--tools/js-optimizer.js73
1 files changed, 50 insertions, 23 deletions
diff --git a/tools/js-optimizer.js b/tools/js-optimizer.js
index 4192ddd1..e61317af 100644
--- a/tools/js-optimizer.js
+++ b/tools/js-optimizer.js
@@ -801,7 +801,10 @@ function simplifyExpressions(ast) {
// HEAP[x >> 2]
// very often. We can in some cases do the shift on the variable itself when it is set,
// to greatly reduce the number of shift operations.
-// TODO: when shifting a variable, if there are other uses, keep an unshifted version too, to prevent slowdowns?
+// XXX this optimization is deprecated and currently invalid: does not handle overflows
+// or non-aligned (round numbers, x >> 2 is a multiple of 4). Both are ok to assume
+// for pointers (undefined behavior otherwise), but invalid in general, and we do
+// no sufficiently-well distinguish the cases.
function optimizeShiftsInternal(ast, conservative) {
var MAX_SHIFTS = 3;
traverseGeneratedFunctions(ast, function(fun) {
@@ -3001,7 +3004,7 @@ function outline(ast) {
// Try to flatten out code as much as possible, to make outlining more feasible.
function flatten(func, asmData) {
- var minSize = sizeToOutline;
+ var minSize = extraInfo.sizeToOutline/4;
var helperId = 0;
function getHelper() {
while (1) {
@@ -3106,7 +3109,9 @@ function outline(ast) {
// Reserve an extra two spots per possible outlining: one for control flow var, the other for control flow data
// The control variables are zeroed out when calling an outlined function, and after using
// the value after they return.
- asmData.maxOutlinings = Math.round(3*measureSize(func)/extraInfo.sizeToOutline);
+ var size = measureSize(func);
+ asmData.maxOutlinings = Math.round(3*size/extraInfo.sizeToOutline);
+ asmData.intendedPieces = Math.ceil(size/extraInfo.sizeToOutline);
asmData.totalStackSize = stackSize + (stack.length + 2*asmData.maxOutlinings)*8;
asmData.controlStackPos = function(i) { return stackSize + (stack.length + i)*8 };
asmData.controlDataStackPos = function(i) { return stackSize + (stack.length + i)*8 + 4 };
@@ -3211,16 +3216,18 @@ function outline(ast) {
var CONTROL_BREAK = 1, CONTROL_BREAK_LABEL = 2, CONTROL_CONTINUE = 3, CONTROL_CONTINUE_LABEL = 4, CONTROL_RETURN_VOID = 5, CONTROL_RETURN_INT = 6, CONTROL_RETURN_DOUBLE = 7;
var sizeToOutline = null; // customized per function and as we make progress
- function calculateThreshold(func) {
- sizeToOutline = extraInfo.sizeToOutline;
+ function calculateThreshold(func, asmData) {
var size = measureSize(func);
- //var desiredChunks = Math.ceil(size/extraInfo.sizeToOutline);
- ////sizeToOutline = Math.round((extraInfo.sizeToOutline + (2*size/desiredChunks))/3);
- //sizeToOutline = Math.round(size/desiredChunks);
- printErr('trying to reduce the size of ' + func[1] + ' which is ' + size + ' (>= ' + extraInfo.sizeToOutline + '), aim for ' + sizeToOutline);
+ if (size <= extraInfo.sizeToOutline) {
+ sizeToOutline = Infinity;
+ printErr(' no point in trying to reduce the size of ' + func[1] + ' which is ' + size + ' <= ' + extraInfo.sizeToOutline);
+ } else {
+ sizeToOutline = Math.round(size/Math.max(2, asmData.intendedPieces--));
+ printErr('trying to reduce the size of ' + func[1] + ' which is ' + size + ' (>=? ' + extraInfo.sizeToOutline + '), aim for ' + sizeToOutline);
+ }
}
- var level = 0;
+ var level = 0, loops = 0;
var outliningParents = {}; // function name => parent it was outlined from
function doOutline(func, asmData, stats, start, end) {
@@ -3241,21 +3248,29 @@ function outline(ast) {
}
});
var reps = [];
- // wipe out control variable
- reps.push(['stat', makeAssign(makeStackAccess(ASM_INT, asmData.controlStackPos(outlineIndex)), ['num', 0])]);
- reps.push(['stat', makeAssign(makeStackAccess(ASM_INT, asmData.controlDataStackPos(outlineIndex)), ['num', 0])]); // XXX not really needed
- // add spills and reads before and after the call to the outlined code, and in the outlined code itself
- keys(setUnion(codeInfo.reads, codeInfo.writes)).forEach(function(v) {
+ // add spills
+ function orderFunc(x, y) {
+ return (asmData.stackPos[x] - asmData.stackPos[y]) || x.localeCompare(y);
+ }
+ var sortedReadsAndWrites = keys(setUnion(codeInfo.reads, codeInfo.writes)).sort(orderFunc);
+ var sortedWrites = keys(codeInfo.writes).sort(orderFunc);
+ sortedReadsAndWrites.forEach(function(v) {
if (!(v in owned)) {
reps.push(['stat', ['assign', true, ['sub', ['name', getAsmType(v, asmData) == ASM_INT ? 'HEAP32' : 'HEAPF32'], ['binary', '>>', ['binary', '+', ['name', 'sp'], ['num', asmData.stackPos[v]]], ['num', '2']]], ['name', v]]]);
}
});
+ // wipe out control variable
+ reps.push(['stat', makeAssign(makeStackAccess(ASM_INT, asmData.controlStackPos(outlineIndex)), ['num', 0])]);
+ reps.push(['stat', makeAssign(makeStackAccess(ASM_INT, asmData.controlDataStackPos(outlineIndex)), ['num', 0])]); // XXX not really needed
+ // do the call
reps.push(['stat', ['call', ['name', newIdent], [['name', 'sp']]]]);
- for (var v in codeInfo.writes) {
+ // add unspills
+ sortedWrites.forEach(function(v) {
if (!(v in owned)) {
reps.push(['stat', ['assign', true, ['name', v], makeAsmCoercion(['sub', ['name', getAsmType(v, asmData) == ASM_INT ? 'HEAP32' : 'HEAPF32'], ['binary', '>>', ['binary', '+', ['name', 'sp'], ['num', asmData.stackPos[v]]], ['num', '2']]], getAsmType(v, asmData))]]);
}
- }
+ });
+
// Generate new function
if (codeInfo.hasReturn || codeInfo.hasReturnInt || codeInfo.hasReturnDouble || codeInfo.hasBreak || codeInfo.hasContinue) {
// we need to capture all control flow using a top-level labeled one-time loop in the outlined function
@@ -3389,16 +3404,17 @@ function outline(ast) {
}
}
// add spills and unspills in outlined code outside the OL loop
- keys(setUnion(codeInfo.reads, codeInfo.writes)).forEach(function(v) {
+ sortedReadsAndWrites.reverse();
+ sortedReadsAndWrites.forEach(function(v) {
if (!(v in owned)) {
code.unshift(['stat', ['assign', true, ['name', v], makeAsmCoercion(['sub', ['name', getAsmType(v, asmData) == ASM_INT ? 'HEAP32' : 'HEAPF32'], ['binary', '>>', ['binary', '+', ['name', 'sp'], ['num', asmData.stackPos[v]]], ['num', '2']]], getAsmType(v, asmData))]]);
}
});
- for (var v in codeInfo.writes) {
+ sortedWrites.forEach(function(v) {
if (!(v in owned)) {
code.push(['stat', ['assign', true, ['sub', ['name', getAsmType(v, asmData) == ASM_INT ? 'HEAP32' : 'HEAPF32'], ['binary', '>>', ['binary', '+', ['name', 'sp'], ['num', asmData.stackPos[v]]], ['num', '2']]], ['name', v]]]);
}
- }
+ });
// finalize
var newFunc = ['defun', newIdent, ['sp'], code];
var newAsmData = { params: { sp: ASM_INT }, vars: {} };
@@ -3436,8 +3452,8 @@ function outline(ast) {
}
}
outliningParents[newIdent] = func[1];
- printErr('performed outline ' + [func[1], newIdent, 'code sizes (pre/post):', originalCodeSize, measureSize(code), 'overhead (w/r):', setSize(setSub(codeInfo.writes, owned)), setSize(setSub(codeInfo.reads, owned))]);
- calculateThreshold(func);
+ printErr('performed outline ' + [func[1], newIdent, 'code sizes (pre/post):', originalCodeSize, measureSize(code), 'overhead (w/r):', setSize(setSub(codeInfo.writes, owned)), setSize(setSub(codeInfo.reads, owned)), ' owned: ', setSize(owned), ' left: ', setSize(asmData.vars), setSize(asmData.params), ' loopsDepth: ', loops]);
+ calculateThreshold(func, asmData);
return [newFunc];
}
@@ -3462,6 +3478,9 @@ function outline(ast) {
}
}
}
+ function done() {
+ return asmData.splitCounter >= asmData.maxOutlinings || measureSize(func) <= extraInfo.sizeToOutline;
+ }
while (1) {
i--;
calcMinIndex(); // TODO: optimize
@@ -3506,11 +3525,18 @@ function outline(ast) {
if (subRet && subRet.length > 0) ret.push.apply(ret, subRet);
}
return null; // do not recurse into children, outlineStatements will do so if necessary
+ } else if (type == 'while') {
+ loops++;
+ }
+ }, function(node, type) {
+ if (type == 'while') {
+ loops--;
}
});
if (ret.length > pre) {
// we outlined recursively, reset our state here
//printErr('successful outline in recursion ' + func[1] + ' due to recursive in level ' + level);
+ if (done()) break;
end = i-1;
sizeSeen = 0;
canRestart = true;
@@ -3550,6 +3576,7 @@ function outline(ast) {
if (newFuncs.length) {
ret.push.apply(ret, newFuncs);
}
+ if (done()) break;
sizeSeen = 0;
end = i-1;
canRestart = true;
@@ -3581,8 +3608,8 @@ function outline(ast) {
if (size >= extraInfo.sizeToOutline) {
aggressiveVariableElimination(func, asmData);
flatten(func, asmData);
- calculateThreshold(func);
analyzeFunction(func, asmData);
+ calculateThreshold(func, asmData);
var stats = getStatements(func);
var ret = outlineStatements(func, asmData, stats, 0.9*size);
assert(level == 0);
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2025-07-27 17:21:27 +0000