Revision 0725ff3edc2ddddbd126193ca8ccaf392044b5ab authored by Bruce Mitchener on 25 September 2013, 04:58:12 UTC, committed by Bruce Mitchener on 25 September 2013, 23:46:53 UTC
1 parent 894d13a
analyzer.js
//"use strict";
// Analyze intertype data. Calculates things that are necessary in order
// to do the final conversion into JavaScript later, for example,
// properties of variables, loop structures of functions, etc.
var VAR_NATIVE = 'native';
var VAR_NATIVIZED = 'nativized';
var VAR_EMULATED = 'emulated';
var ENTRY_IDENT = toNiceIdent('%0');
function recomputeLines(func) {
func.lines = func.labels.map(function(label) { return label.lines }).reduce(concatenator, []);
}
// Handy sets
var BRANCH_INVOKE = set('branch', 'invoke');
var LABEL_ENDERS = set('branch', 'return', 'switch');
var SIDE_EFFECT_CAUSERS = set('call', 'invoke', 'atomic');
var UNUNFOLDABLE = set('value', 'structvalue', 'type', 'phiparam');
var SHADOW_FLIP = { i64: 'double', double: 'i64' }; //, i32: 'float', float: 'i32' };
// Analyzer
function analyzer(data, sidePass) {
var mainPass = !sidePass;
var item = { items: data };
var data = item;
// Gather
// Single-liners
['globalVariable', 'functionStub', 'unparsedFunction', 'unparsedGlobals', 'unparsedTypes', 'alias'].forEach(function(intertype) {
var temp = splitter(item.items, function(item) { return item.intertype == intertype });
item.items = temp.leftIn;
item[intertype + 's'] = temp.splitOut;
});
var temp = splitter(item.items, function(item) { return item.intertype == 'type' });
item.items = temp.leftIn;
temp.splitOut.forEach(function(type) {
//dprint('types', 'adding defined type: ' + type.name_);
Types.types[type.name_] = type;
if (QUANTUM_SIZE === 1) {
Types.fatTypes[type.name_] = copy(type);
}
});
// Functions & labels
item.functions = [];
var currLabelFinished = false; // Sometimes LLVM puts a branch in the middle of a label. We need to ignore all lines after that.
item.items.sort(function(a, b) { return a.lineNum - b.lineNum });
for (var i = 0; i < item.items.length; i++) {
var subItem = item.items[i];
assert(subItem.lineNum);
if (subItem.intertype == 'function') {
item.functions.push(subItem);
subItem.endLineNum = null;
subItem.lines = []; // We will fill in the function lines after the legalizer, since it can modify them
subItem.labels = [];
subItem.forceEmulated = false;
// no explicit 'entry' label in clang on LLVM 2.8 - most of the time, but not all the time! - so we add one if necessary
if (item.items[i+1].intertype !== 'label') {
item.items.splice(i+1, 0, {
intertype: 'label',
ident: ENTRY_IDENT,
lineNum: subItem.lineNum + '.5'
});
}
} else if (subItem.intertype == 'functionEnd') {
item.functions.slice(-1)[0].endLineNum = subItem.lineNum;
} else if (subItem.intertype == 'label') {
item.functions.slice(-1)[0].labels.push(subItem);
subItem.lines = [];
currLabelFinished = false;
} else if (item.functions.length > 0 && item.functions.slice(-1)[0].endLineNum === null) {
// Internal line
if (!currLabelFinished) {
item.functions.slice(-1)[0].labels.slice(-1)[0].lines.push(subItem); // If this line fails, perhaps missing a label?
if (subItem.intertype in LABEL_ENDERS) {
currLabelFinished = true;
}
} else {
print('// WARNING: content after a branch in a label, line: ' + subItem.lineNum);
}
} else {
throw 'ERROR: what is this? ' + dump(subItem);
}
}
delete item.items;
// CastAway - try to remove bitcasts of double<-->i64, which LLVM sometimes generates unnecessarily
// (load a double, convert to i64, use as i64).
// We optimize this by checking if there are such bitcasts. If so we create a shadow
// variable that is of the other type, and use that in the relevant places. (As SSA, this is valid, and
// variable elimination later will remove the double load if it is no longer needed.)
//
// Note that aside from being an optimization, this is needed for correctness in some cases: If code
// assumes it can bitcast a double to an i64 and back and forth without loss, that may be violated
// due to NaN canonicalization.
function castAway() {
if (USE_TYPED_ARRAYS != 2) return;
item.functions.forEach(function(func) {
var has = false;
func.labels.forEach(function(label) {
var lines = label.lines;
for (var i = 0; i < lines.length; i++) {
var line = lines[i];
if (line.intertype == 'bitcast' && line.type in SHADOW_FLIP) {
has = true;
}
}
});
if (!has) return;
// there are integer<->floating-point bitcasts, create shadows for everything
var shadowed = {};
func.labels.forEach(function(label) {
var lines = label.lines;
var i = 0;
while (i < lines.length) {
var lines = label.lines;
var line = lines[i];
if (line.intertype == 'load' && line.type in SHADOW_FLIP) {
if (line.pointer.intertype != 'value') { i++; continue } // TODO
shadowed[line.assignTo] = 1;
var shadow = line.assignTo + '$$SHADOW';
var flip = SHADOW_FLIP[line.type];
lines.splice(i + 1, 0, { // if necessary this element will be legalized in the next phase
tokens: null,
indent: 2,
lineNum: line.lineNum + 0.5,
assignTo: shadow,
intertype: 'load',
pointerType: flip + '*',
type: flip,
valueType: flip,
pointer: {
intertype: 'value',
ident: line.pointer.ident,
type: flip + '*'
},
align: line.align,
ident: line.ident
});
// note: no need to update func.lines, it is generated in a later pass
i++;
}
i++;
}
});
// use shadows where possible
func.labels.forEach(function(label) {
var lines = label.lines;
for (var i = 0; i < lines.length; i++) {
var line = lines[i];
if (line.intertype == 'bitcast' && line.type in SHADOW_FLIP && line.ident in shadowed) {
var shadow = line.ident + '$$SHADOW';
line.params[0].ident = shadow;
line.params[0].type = line.type;
line.type2 = line.type;
}
}
});
});
}
// Legalize LLVM unrealistic types into realistic types.
//
// With full LLVM optimizations, it can generate types like i888 which do not exist in
// any actual hardware implementation, but are useful during optimization. LLVM then
// legalizes these types into real ones during code generation. Sadly, there is no LLVM
// IR pass to legalize them, which would have been useful and nice from a design perspective.
// The LLVM community is also not interested in receiving patches to implement that
// functionality, since it would duplicate existing code from the code generation
// component. Therefore, we implement legalization here in Emscripten.
//
// Currently we just legalize completely unrealistic types into bundles of i32s, and just
// the most common instructions that can be involved with such types: load, store, shifts,
// trunc and zext.
function legalizer() {
// Legalization
if (USE_TYPED_ARRAYS == 2) {
function getLegalVars(base, bits, allowLegal) {
bits = bits || 32; // things like pointers are all i32, but show up as 0 bits from getBits
if (allowLegal && bits <= 32) return [{ ident: base + ('i' + bits in Runtime.INT_TYPES ? '' : '$0'), bits: bits }];
if (isNumber(base)) return getLegalLiterals(base, bits);
if (base[0] == '{') {
warnOnce('seeing source of illegal data ' + base + ', likely an inline struct - assuming zeroinit');
return getLegalLiterals('0', bits);
}
var ret = new Array(Math.ceil(bits/32));
var i = 0;
if (base == 'zeroinitializer' || base == 'undef') base = 0;
while (bits > 0) {
ret[i] = { ident: base ? base + '$' + i : '0', bits: Math.min(32, bits) };
bits -= 32;
i++;
}
return ret;
}
function getLegalLiterals(text, bits) {
var parsed = parseArbitraryInt(text, bits);
var ret = new Array(Math.ceil(bits/32));
var i = 0;
while (bits > 0) {
ret[i] = { ident: (parsed[i]|0).toString(), bits: Math.min(32, bits) }; // resign all values
bits -= 32;
i++;
}
return ret;
}
function getLegalStructuralParts(value) {
return value.params.slice(0);
}
function getLegalParams(params, bits) {
return params.map(function(param) {
var value = param.value || param;
if (isNumber(value.ident)) {
return getLegalLiterals(value.ident, bits);
} else if (value.intertype == 'structvalue') {
return getLegalStructuralParts(value).map(function(part) {
return { ident: part.ident, bits: part.type.substr(1) };
});
} else {
return getLegalVars(value.ident, bits);
}
});
}
// Uses the right factor to multiply line numbers by so that they fit in between
// the line[i] and the line after it
function interpLines(lines, i, toAdd) {
var prev = i >= 0 ? lines[i].lineNum : -1;
var next = (i < lines.length-1) ? lines[i+1].lineNum : (lines[i].lineNum + 0.5);
var factor = (next - prev)/(4*toAdd.length+3);
for (var k = 0; k < toAdd.length; k++) {
toAdd[k].lineNum = prev + ((k+1)*factor);
assert(k == 0 || toAdd[k].lineNum > toAdd[k-1].lineNum);
}
}
function removeAndAdd(lines, i, toAdd) {
var item = lines[i];
interpLines(lines, i, toAdd);
Array.prototype.splice.apply(lines, [i, 1].concat(toAdd));
if (i > 0) assert(lines[i].lineNum > lines[i-1].lineNum);
if (i + toAdd.length < lines.length) assert(lines[i + toAdd.length - 1].lineNum < lines[i + toAdd.length].lineNum);
return toAdd.length;
}
function legalizeFunctionParameters(params) {
var i = 0;
while (i < params.length) {
var param = params[i];
if (param.intertype == 'value' && isIllegalType(param.type)) {
var toAdd = getLegalVars(param.ident, getBits(param.type)).map(function(element) {
return {
intertype: 'value',
type: 'i' + element.bits,
ident: element.ident,
byval: 0
};
});
Array.prototype.splice.apply(params, [i, 1].concat(toAdd));
i += toAdd.length;
continue;
} else if (param.intertype == 'structvalue') {
// 'flatten' out the struct into scalars
var toAdd = param.params;
toAdd.forEach(function(param) {
param.byval = 0;
});
Array.prototype.splice.apply(params, [i, 1].concat(toAdd));
continue; // do not increment i; proceed to process the new params
}
i++;
}
}
function fixUnfolded(item) {
// Unfolded items may need some correction to work properly in the global scope
if (item.intertype in MATHOPS) {
item.op = item.intertype;
item.intertype = 'mathop';
}
}
data.functions.forEach(function(func) {
// Legalize function params
legalizeFunctionParameters(func.params);
// Legalize lines in labels
var tempId = 0;
func.labels.forEach(function(label) {
if (dcheck('legalizer')) dprint('zz legalizing: \n' + dump(label.lines));
var i = 0, bits;
while (i < label.lines.length) {
var item = label.lines[i];
var value = item;
// Check if we need to legalize here, and do some trivial legalization along the way
var isIllegal = false;
walkInterdata(item, function(item) {
if (item.intertype == 'getelementptr' || (item.intertype == 'call' && item.ident in LLVM.INTRINSICS_32)) {
// Turn i64 args into i32
for (var i = 0; i < item.params.length; i++) {
if (item.params[i].type == 'i64') item.params[i].type = 'i32';
}
} else if (item.intertype == 'inttoptr') {
var input = item.params[0];
if (input.type == 'i64') input.type = 'i32'; // inttoptr can only care about 32 bits anyhow since pointers are 32-bit
}
if (isIllegalType(item.valueType) || isIllegalType(item.type)) {
isIllegal = true;
} else if ((item.intertype == 'load' || item.intertype == 'store') && isStructType(item.valueType)) {
isIllegal = true; // storing an entire structure is illegal
} else if (item.intertype == 'mathop' && item.op == 'trunc' && isIllegalType(item.params[1].ident)) { // trunc stores target value in second ident
isIllegal = true;
}
});
if (!isIllegal) {
//if (dcheck('legalizer')) dprint('no need to legalize \n' + dump(item));
i++;
continue;
}
// Unfold this line. If we unfolded, we need to return and process the lines we just
// generated - they may need legalization too
var unfolded = [];
walkAndModifyInterdata(item, function(subItem) {
// Unfold all non-value interitems that we can, and also unfold all numbers (doing the latter
// makes it easier later since we can then assume illegal expressions are always variables
// accessible through ident$x, and not constants we need to parse then and there)
if (subItem != item && (!(subItem.intertype in UNUNFOLDABLE) ||
(subItem.intertype == 'value' && isNumber(subItem.ident) && isIllegalType(subItem.type)))) {
if (item.intertype == 'phi') {
assert(subItem.intertype == 'value' || subItem.intertype == 'structvalue' || subItem.intertype in PARSABLE_LLVM_FUNCTIONS, 'We can only unfold some expressions in phis');
// we must handle this in the phi itself, if we unfold normally it will not be pushed back with the phi
} else {
var tempIdent = '$$etemp$' + (tempId++);
subItem.assignTo = tempIdent;
unfolded.unshift(subItem);
fixUnfolded(subItem);
return { intertype: 'value', ident: tempIdent, type: subItem.type };
}
} else if (subItem.intertype == 'switch' && isIllegalType(subItem.type)) {
subItem.switchLabels.forEach(function(switchLabel) {
if (switchLabel.value[0] != '$') {
var tempIdent = '$$etemp$' + (tempId++);
unfolded.unshift({
assignTo: tempIdent,
intertype: 'value',
ident: switchLabel.value,
type: subItem.type
});
switchLabel.value = tempIdent;
}
});
}
});
if (unfolded.length > 0) {
interpLines(label.lines, i-1, unfolded);
Array.prototype.splice.apply(label.lines, [i, 0].concat(unfolded));
continue; // remain at this index, to unfold newly generated lines
}
// This is an illegal-containing line, and it is unfolded. Legalize it now
dprint('legalizer', 'Legalizing ' + item.intertype + ' at line ' + item.lineNum);
var finalizer = null;
switch (item.intertype) {
case 'store': {
var toAdd = [];
bits = getBits(item.valueType);
var elements = getLegalParams([item.value], bits)[0];
var j = 0;
elements.forEach(function(element) {
var tempVar = '$st$' + (tempId++) + '$' + j;
toAdd.push({
intertype: 'getelementptr',
assignTo: tempVar,
ident: item.pointer.ident,
type: '[0 x i32]*',
params: [
{ intertype: 'value', ident: item.pointer.ident, type: '[0 x i32]*' }, // technically a bitcase is needed in llvm, but not for us
{ intertype: 'value', ident: '0', type: 'i32' },
{ intertype: 'value', ident: j.toString(), type: 'i32' }
],
});
var actualSizeType = 'i' + element.bits; // The last one may be smaller than 32 bits
toAdd.push({
intertype: 'store',
valueType: actualSizeType,
value: { intertype: 'value', ident: element.ident, type: actualSizeType },
pointer: { intertype: 'value', ident: tempVar, type: actualSizeType + '*' },
ident: tempVar,
pointerType: actualSizeType + '*',
align: item.align,
});
j++;
});
Types.needAnalysis['[0 x i32]'] = 0;
i += removeAndAdd(label.lines, i, toAdd);
continue;
}
// call, return: Return the first 32 bits, the rest are in temp
case 'call': {
var toAdd = [value];
// legalize parameters
legalizeFunctionParameters(value.params);
// legalize return value, if any
var returnType = getReturnType(item.type);
if (value.assignTo && isIllegalType(returnType)) {
bits = getBits(returnType);
var elements = getLegalVars(item.assignTo, bits);
// legalize return value
value.assignTo = elements[0].ident;
for (var j = 1; j < elements.length; j++) {
var element = elements[j];
toAdd.push({
intertype: 'value',
assignTo: element.ident,
type: element.bits,
ident: 'tempRet' + (j - 1)
});
assert(j<10); // TODO: dynamically create more than 10 tempRet-s
}
}
i += removeAndAdd(label.lines, i, toAdd);
continue;
}
case 'landingpad': {
// not much to legalize
i++;
continue;
}
case 'return': {
bits = getBits(item.type);
var elements = getLegalVars(item.value.ident, bits);
item.value.ident = '(';
for (var j = 1; j < elements.length; j++) {
item.value.ident += 'tempRet' + (j-1) + '=' + elements[j].ident + ',';
}
item.value.ident += elements[0].ident + ')';
i++;
continue;
}
case 'invoke': {
legalizeFunctionParameters(value.params);
// We can't add lines after this, since invoke already modifies control flow. So we handle the return in invoke
i++;
continue;
}
case 'value': {
bits = getBits(value.type);
var elements = getLegalVars(item.assignTo, bits);
var values = getLegalLiterals(item.ident, bits);
var j = 0;
var toAdd = elements.map(function(element) {
return {
intertype: 'value',
assignTo: element.ident,
type: 'i' + bits,
ident: values[j++].ident
};
});
i += removeAndAdd(label.lines, i, toAdd);
continue;
}
case 'structvalue': {
bits = getBits(value.type);
var elements = getLegalVars(item.assignTo, bits);
var toAdd = [];
for (var j = 0; j < item.params.length; j++) {
toAdd[j] = {
intertype: 'value',
assignTo: elements[j].ident,
type: 'i32',
ident: item.params[j].ident
};
}
i += removeAndAdd(label.lines, i, toAdd);
continue;
}
case 'load': {
bits = getBits(value.valueType);
var elements = getLegalVars(item.assignTo, bits);
var j = 0;
var toAdd = [];
elements.forEach(function(element) {
var tempVar = '$ld$' + (tempId++) + '$' + j;
toAdd.push({
intertype: 'getelementptr',
assignTo: tempVar,
ident: value.pointer.ident,
type: '[0 x i32]*',
params: [
{ intertype: 'value', ident: value.pointer.ident, type: '[0 x i32]*' }, // technically bitcast is needed in llvm, but not for us
{ intertype: 'value', ident: '0', type: 'i32' },
{ intertype: 'value', ident: j.toString(), type: 'i32' }
]
});
var newItem = {
intertype: 'load',
assignTo: element.ident,
pointerType: 'i32*',
valueType: 'i32',
type: 'i32',
pointer: { intertype: 'value', ident: tempVar, type: 'i32*' },
ident: tempVar,
align: value.align
};
var newItem2 = null;
// The last one may be smaller than 32 bits
if (element.bits < 32) {
newItem.assignTo += '$preadd$';
newItem2 = {
intertype: 'mathop',
op: 'and',
assignTo: element.ident,
type: 'i32',
params: [{
intertype: 'value',
type: 'i32',
ident: newItem.assignTo
}, {
intertype: 'value',
type: 'i32',
ident: (0xffffffff >>> (32 - element.bits)).toString()
}],
};
}
toAdd.push(newItem);
if (newItem2) toAdd.push(newItem2);
j++;
});
Types.needAnalysis['[0 x i32]'] = 0;
i += removeAndAdd(label.lines, i, toAdd);
continue;
}
case 'phi': {
bits = getBits(value.type);
var toAdd = [];
var elements = getLegalVars(item.assignTo, bits);
var j = 0;
var values = getLegalParams(value.params, bits);
elements.forEach(function(element) {
var k = 0;
toAdd.push({
intertype: 'phi',
assignTo: element.ident,
type: 'i' + element.bits,
params: value.params.map(function(param) {
return {
intertype: 'phiparam',
label: param.label,
value: {
intertype: 'value',
ident: values[k++][j].ident,
type: 'i' + element.bits,
}
};
})
});
j++;
});
i += removeAndAdd(label.lines, i, toAdd);
continue;
}
case 'switch': {
i++;
continue; // special case, handled in makeComparison
}
case 'va_arg': {
assert(value.type == 'i64');
assert(value.value.type == 'i32*', value.value.type);
i += removeAndAdd(label.lines, i, range(2).map(function(x) {
return {
intertype: 'va_arg',
assignTo: value.assignTo + '$' + x,
type: 'i32',
value: {
intertype: 'value',
ident: value.value.ident, // We read twice from the same i32* var, incrementing // + '$' + x,
type: 'i32*'
}
};
}));
continue;
}
case 'extractvalue': { // XXX we assume 32-bit alignment in extractvalue/insertvalue,
// but in theory they can run on packed structs too (see use getStructuralTypePartBits)
// potentially legalize the actual extracted value too if it is >32 bits, not just the extraction in general
var index = item.indexes[0][0].text;
var parts = getStructureTypeParts(item.type);
var indexedType = parts[index];
var targetBits = getBits(indexedType);
var sourceBits = getBits(item.type);
var elements = getLegalVars(item.assignTo, targetBits, true); // possibly illegal
var sourceElements = getLegalVars(item.ident, sourceBits); // definitely illegal
var toAdd = [];
var sourceIndex = 0;
for (var partIndex = 0; partIndex < parts.length; partIndex++) {
if (partIndex == index) {
for (var j = 0; j < elements.length; j++) {
toAdd.push({
intertype: 'value',
assignTo: elements[j].ident,
type: 'i' + elements[j].bits,
ident: sourceElements[sourceIndex+j].ident
});
}
break;
}
sourceIndex += getStructuralTypePartBits(parts[partIndex])/32;
}
i += removeAndAdd(label.lines, i, toAdd);
continue;
}
case 'insertvalue': {
var index = item.indexes[0][0].text; // the modified index
var parts = getStructureTypeParts(item.type);
var indexedType = parts[index];
var indexBits = getBits(indexedType);
var bits = getBits(item.type); // source and target
bits = getBits(value.type);
var toAdd = [];
var elements = getLegalVars(item.assignTo, bits);
var sourceElements = getLegalVars(item.ident, bits);
var indexElements = getLegalVars(item.value.ident, indexBits, true); // possibly legal
var sourceIndex = 0;
for (var partIndex = 0; partIndex < parts.length; partIndex++) {
var currNum = getStructuralTypePartBits(parts[partIndex])/32;
for (var j = 0; j < currNum; j++) {
toAdd.push({
intertype: 'value',
assignTo: elements[sourceIndex+j].ident,
type: 'i' + elements[sourceIndex+j].bits,
ident: partIndex == index ? indexElements[j].ident : sourceElements[sourceIndex+j].ident
});
}
sourceIndex += currNum;
}
i += removeAndAdd(label.lines, i, toAdd);
continue;
}
case 'bitcast': {
var inType = item.type2;
var outType = item.type;
if ((inType in Runtime.INT_TYPES && outType in Runtime.FLOAT_TYPES) ||
(inType in Runtime.FLOAT_TYPES && outType in Runtime.INT_TYPES)) {
i++;
continue; // special case, handled in processMathop
}
// fall through
}
case 'inttoptr': case 'ptrtoint': case 'zext': case 'sext': case 'trunc': case 'ashr': case 'lshr': case 'shl': case 'or': case 'and': case 'xor': {
value = {
op: item.intertype,
variant: item.variant,
type: item.type,
params: item.params
};
// fall through
}
case 'mathop': {
var toAdd = [];
var sourceBits = getBits(value.params[0].type);
// All mathops can be parametrized by how many shifts we do, and how big the source is
var shifts = 0;
var targetBits = sourceBits;
var processor = null;
var signed = false;
switch (value.op) {
case 'ashr': {
signed = true;
// fall through
}
case 'lshr': {
shifts = parseInt(value.params[1].ident);
break;
}
case 'shl': {
shifts = -parseInt(value.params[1].ident);
break;
}
case 'sext': {
signed = true;
// fall through
}
case 'trunc': case 'zext': case 'ptrtoint': {
targetBits = getBits(value.params[1] ? value.params[1].ident : value.type);
break;
}
case 'inttoptr': {
targetBits = 32;
break;
}
case 'bitcast': {
if (!sourceBits) {
// we can be asked to bitcast doubles or such to integers, handle that as best we can (if it's a double that
// was an x86_fp80, this code will likely break when called)
sourceBits = targetBits = Runtime.getNativeTypeSize(value.params[0].type);
warn('legalizing non-integer bitcast on ll #' + item.lineNum);
}
break;
}
case 'select': {
sourceBits = targetBits = getBits(value.params[1].type);
var params = getLegalParams(value.params.slice(1), sourceBits);
processor = function(result, j) {
return {
intertype: 'mathop',
op: 'select',
type: 'i' + params[0][j].bits,
params: [
value.params[0],
{ intertype: 'value', ident: params[0][j].ident, type: 'i' + params[0][j].bits },
{ intertype: 'value', ident: params[1][j].ident, type: 'i' + params[1][j].bits }
]
};
};
break;
}
case 'or': case 'and': case 'xor': case 'icmp': {
var otherElements = getLegalVars(value.params[1].ident, sourceBits);
processor = function(result, j) {
return {
intertype: 'mathop',
op: value.op,
variant: value.variant,
type: 'i' + otherElements[j].bits,
params: [
result,
{ intertype: 'value', ident: otherElements[j].ident, type: 'i' + otherElements[j].bits }
]
};
};
if (value.op == 'icmp') {
if (sourceBits == 64) { // handle the i64 case in processMathOp, where we handle full i64 math
i++;
continue;
}
finalizer = function() {
var ident = '';
for (var i = 0; i < targetElements.length; i++) {
if (i > 0) {
switch(value.variant) {
case 'eq': ident += '&'; break;
case 'ne': ident += '|'; break;
default: throw 'unhandleable illegal icmp: ' + value.variant;
}
}
ident += targetElements[i].ident;
}
return {
intertype: 'value',
ident: ident,
type: 'rawJS',
assignTo: item.assignTo
};
}
}
break;
}
case 'add': case 'sub': case 'sdiv': case 'udiv': case 'mul': case 'urem': case 'srem': {
if (sourceBits < 32) {
// when we add illegal types like i24, we must work on the singleton chunks
item.assignTo += '$0';
item.params[0].ident += '$0';
item.params[1].ident += '$0';
}
// fall through
}
case 'uitofp': case 'sitofp': case 'fptosi': case 'fptoui': {
// We cannot do these in parallel chunks of 32-bit operations. We will handle these in processMathop
i++;
continue;
}
default: throw 'Invalid mathop for legalization: ' + [value.op, item.lineNum, dump(item)];
}
// Do the legalization
var sourceElements = getLegalVars(value.params[0].ident, sourceBits, true);
if (!isNumber(shifts)) {
// We can't statically legalize this, do the operation at runtime TODO: optimize
assert(sourceBits == 64, 'TODO: handle nonconstant shifts on != 64 bits');
assert(PRECISE_I64_MATH, 'Must have precise i64 math for non-constant 64-bit shifts');
Types.preciseI64MathUsed = 1;
value.intertype = 'value';
value.ident = 'var ' + value.assignTo + '$0 = ' +
asmCoercion('_bitshift64' + value.op[0].toUpperCase() + value.op.substr(1) + '(' +
asmCoercion(sourceElements[0].ident, 'i32') + ',' +
asmCoercion(sourceElements[1].ident, 'i32') + ',' +
asmCoercion(value.params[1].ident + '$0', 'i32') + ')', 'i32'
) + ';' +
'var ' + value.assignTo + '$1 = tempRet0;';
value.assignTo = null;
i++;
continue;
}
var targetElements = getLegalVars(item.assignTo, targetBits);
var sign = shifts >= 0 ? 1 : -1;
var shiftOp = shifts >= 0 ? 'shl' : 'lshr';
var shiftOpReverse = shifts >= 0 ? 'lshr' : 'shl';
var whole = shifts >= 0 ? Math.floor(shifts/32) : Math.ceil(shifts/32);
var fraction = Math.abs(shifts % 32);
if (signed) {
var signedFill = '(' + makeSignOp(sourceElements[sourceElements.length-1].ident, 'i' + sourceElements[sourceElements.length-1].bits, 're', 1, 1) + ' < 0 ? -1 : 0)';
var signedKeepAlive = { intertype: 'value', ident: sourceElements[sourceElements.length-1].ident, type: 'i32' };
}
for (var j = 0; j < targetElements.length; j++) {
var result = {
intertype: 'value',
ident: (j + whole >= 0 && j + whole < sourceElements.length) ? sourceElements[j + whole].ident : (signed ? signedFill : '0'),
params: [(signed && j + whole > sourceElements.length) ? signedKeepAlive : null],
type: 'i32',
};
if (j == 0 && sourceBits < 32) {
// zext sign correction
result.ident = makeSignOp(result.ident, 'i' + sourceBits, isUnsignedOp(value.op) ? 'un' : 're', 1, 1);
}
if (fraction != 0) {
var other = {
intertype: 'value',
ident: (j + sign + whole >= 0 && j + sign + whole < sourceElements.length) ? sourceElements[j + sign + whole].ident : (signed ? signedFill : '0'),
params: [(signed && j + sign + whole > sourceElements.length) ? signedKeepAlive : null],
type: 'i32',
};
other = {
intertype: 'mathop',
op: shiftOp,
type: 'i32',
params: [
other,
{ intertype: 'value', ident: (32 - fraction).toString(), type: 'i32' }
]
};
result = {
intertype: 'mathop',
// shifting in 1s from the top is a special case
op: (signed && shifts >= 0 && j + sign + whole >= sourceElements.length) ? 'ashr' : shiftOpReverse,
type: 'i32',
params: [
result,
{ intertype: 'value', ident: fraction.toString(), type: 'i32' }
]
};
result = {
intertype: 'mathop',
op: 'or',
type: 'i32',
params: [
result,
other
]
}
}
if (targetElements[j].bits < 32 && shifts < 0) {
// truncate bits that fall off the end. This is not needed in most cases, can probably be optimized out
result = {
intertype: 'mathop',
op: 'and',
type: 'i32',
params: [
result,
{ intertype: 'value', ident: (Math.pow(2, targetElements[j].bits)-1).toString(), type: 'i32' }
]
}
}
if (processor) {
result = processor(result, j);
}
result.assignTo = targetElements[j].ident;
toAdd.push(result);
}
if (targetBits <= 32) {
// We are generating a normal legal type here
legalValue = {
intertype: 'value',
ident: targetElements[0].ident + (targetBits < 32 ? '&' + (Math.pow(2, targetBits)-1) : ''),
type: 'rawJS'
};
legalValue.assignTo = item.assignTo;
toAdd.push(legalValue);
} else if (finalizer) {
toAdd.push(finalizer());
}
i += removeAndAdd(label.lines, i, toAdd);
continue;
}
}
assert(0, 'Could not legalize illegal line: ' + [item.lineNum, dump(item)]);
}
if (dcheck('legalizer')) dprint('zz legalized: \n' + dump(label.lines));
});
});
}
// Add function lines to func.lines, after our modifications to the label lines
data.functions.forEach(function(func) {
func.labels.forEach(function(label) {
func.lines = func.lines.concat(label.lines);
});
});
}
function addTypeInternal(type, data) {
if (type.length == 1) return;
if (Types.types[type]) return;
if (['internal', 'hidden', 'inbounds', 'void'].indexOf(type) != -1) return;
if (Runtime.isNumberType(type)) return;
dprint('types', 'Adding type: ' + type);
// 'blocks': [14 x %struct.X] etc. If this is a pointer, we need
// to look at the underlying type - it was not defined explicitly
// anywhere else.
var nonPointing = removeAllPointing(type);
var check = /^\[(\d+)\ x\ (.*)\]$/.exec(nonPointing);
if (check && !Types.types[nonPointing]) {
var num = parseInt(check[1]);
num = Math.max(num, 1); // [0 x something] is used not for allocations and such of course, but
// for indexing - for an |array of unknown length|, basically. So we
// define the 'type' as having a single field. TODO: Ensure as a sanity
// check that we never allocate with this (either as a child structure
// in the analyzer, or in calcSize in alloca).
var subType = check[2];
addTypeInternal(subType, data); // needed for anonymous structure definitions (see below)
// Huge structural types are represented very inefficiently, both here and in generated JS. Best to avoid them - for example static char x[10*1024*1024]; is bad, while static char *x = malloc(10*1024*1024) is fine.
if (num >= 10*1024*1024) warnOnce('warning: very large fixed-size structural type: ' + type + ' - can you reduce it? (compilation may be slow)');
Types.types[nonPointing] = {
name_: nonPointing,
fields: range(num).map(function() { return subType }),
lineNum: '?'
};
// Also add a |[0 x type]| type
var zerod = '[0 x ' + subType + ']';
if (!Types.types[zerod]) {
Types.types[zerod] = {
name_: zerod,
fields: [subType, subType], // Two, so we get the flatFactor right. We care about the flatFactor, not the size here
lineNum: '?'
};
}
return;
}
// anonymous structure definition, for example |{ i32, i8*, void ()*, i32 }|
if (type[0] == '{' || type[0] == '<') {
type = nonPointing;
var packed = type[0] == '<';
var internal = type;
if (packed) {
if (internal[internal.length-1] != '>') {
warnOnce('ignoring type ' + internal);
return; // function pointer or such
}
internal = internal.substr(1, internal.length-2);
}
assert(internal[0] == '{', internal);
if (internal[internal.length-1] != '}') {
warnOnce('ignoring type ' + internal);
return; // function pointer or such
}
internal = internal.substr(2, internal.length-4);
Types.types[type] = {
name_: type,
fields: splitTokenList(tokenize(internal).tokens).map(function(segment) {
return segment[0].text;
}),
packed: packed,
lineNum: '?'
};
return;
}
if (isPointerType(type)) return;
if (['['].indexOf(type) != -1) return;
Types.types[type] = {
name_: type,
fields: [ 'i' + (QUANTUM_SIZE*8) ], // a single quantum size
flatSize: 1,
lineNum: '?'
};
}
function addType(type, data) {
addTypeInternal(type, data);
if (QUANTUM_SIZE === 1) {
Types.flipTypes();
addTypeInternal(type, data);
Types.flipTypes();
}
}
// Typevestigator
function typevestigator() {
if (sidePass) { // Do not investigate in the main pass - it is only valid to start to do so in the first side pass,
// which handles type definitions, and later. Doing so before the first side pass will result in
// making bad guesses about types which are actually defined
for (var type in Types.needAnalysis) {
if (type) addType(type, data);
}
Types.needAnalysis = {};
}
}
// Type analyzer
function analyzeTypes(fatTypes) {
var types = Types.types;
// 'fields' is the raw list of LLVM fields. However, we embed
// child structures into parent structures, basically like C.
// So { int, { int, int }, int } would be represented as
// an Array of 4 ints. getelementptr on the parent would take
// values 0, 1, 2, where 2 is the entire middle structure.
// We also need to be careful with getelementptr to child
// structures - we return a pointer to the same slab, just
// a different offset. Likewise, need to be careful for
// getelementptr of 2 (the last int) - it's real index is 4.
// The benefit of this approach is inheritance -
// { { ancestor } , etc. } = descendant
// In this case it is easy to bitcast ancestor to descendant
// pointers - nothing needs to be done. If the ancestor were
// a new slab, it would need some pointer to the outer one
// for casting in that direction.
// TODO: bitcasts of non-inheritance cases of embedding (not at start)
var more = true;
while (more) {
more = false;
for (var typeName in types) {
var type = types[typeName];
if (type.flatIndexes) continue;
var ready = true;
type.fields.forEach(function(field) {
if (isStructType(field)) {
if (!types[field]) {
addType(field, item);
ready = false;
} else {
if (!types[field].flatIndexes) {
ready = false;
}
}
}
});
if (!ready) {
more = true;
continue;
}
Runtime.calculateStructAlignment(type);
if (dcheck('types')) dprint('type (fat=' + !!fatTypes + '): ' + type.name_ + ' : ' + JSON.stringify(type.fields));
if (dcheck('types')) dprint(' has final size of ' + type.flatSize + ', flatting: ' + type.needsFlattening + ' ? ' + (type.flatFactor ? type.flatFactor : JSON.stringify(type.flatIndexes)));
}
}
if (QUANTUM_SIZE === 1 && !fatTypes) {
Types.flipTypes();
// Fake a quantum size of 4 for fat types. TODO: Might want non-4 for some reason?
var trueQuantumSize = QUANTUM_SIZE;
Runtime.QUANTUM_SIZE = 4;
analyzeTypes(true);
Runtime.QUANTUM_SIZE = trueQuantumSize;
Types.flipTypes();
}
}
// Variable analyzer
function variableAnalyzer() {
// Globals
var old = item.globalVariables;
item.globalVariables = {};
old.forEach(function(variable) {
variable.impl = 'emulated'; // All global variables are emulated, for now. Consider optimizing later if useful
item.globalVariables[variable.ident] = variable;
});
// Function locals
item.functions.forEach(function(func) {
func.variables = {};
// LLVM is SSA, so we always have a single assignment/write. We care about
// the reads/other uses.
// Function parameters
func.params.forEach(function(param) {
if (param.intertype !== 'varargs') {
if (func.variables[param.ident]) warn('cannot have duplicate variable names: ' + param.ident); // toNiceIdent collisions?
func.variables[param.ident] = {
ident: param.ident,
type: param.type,
origin: 'funcparam',
lineNum: func.lineNum,
rawLinesIndex: -1
};
}
});
// Normal variables
func.lines.forEach(function(item, i) {
if (item.assignTo) {
if (func.variables[item.assignTo]) warn('cannot have duplicate variable names: ' + item.assignTo); // toNiceIdent collisions?
var variable = func.variables[item.assignTo] = {
ident: item.assignTo,
type: item.type,
origin: item.intertype,
lineNum: item.lineNum,
rawLinesIndex: i
};
if (variable.origin === 'alloca') {
variable.allocatedNum = item.allocatedNum;
}
if (variable.origin === 'call') {
variable.type = getReturnType(variable.type);
}
}
});
if (QUANTUM_SIZE === 1) {
// Second pass over variables - notice when types are crossed by bitcast
func.lines.forEach(function(item) {
if (item.assignTo && item.intertype === 'bitcast') {
// bitcasts are unique in that they convert one pointer to another. We
// sometimes need to know the original type of a pointer, so we save that.
//
// originalType is the type this variable is created from
// derivedTypes are the types that this variable is cast into
func.variables[item.assignTo].originalType = item.type2;
if (!isNumber(item.assignTo)) {
if (!func.variables[item.assignTo].derivedTypes) {
func.variables[item.assignTo].derivedTypes = [];
}
func.variables[item.assignTo].derivedTypes.push(item.type);
}
}
});
}
// Analyze variable uses
function analyzeVariableUses() {
dprint('vars', 'Analyzing variables for ' + func.ident + '\n');
for (vname in func.variables) {
var variable = func.variables[vname];
// Whether the value itself is used. For an int, always yes. For a pointer,
// we might never use the pointer's value - we might always just store to it /
// read from it. If so, then we can optimize away the pointer.
variable.hasValueTaken = false;
variable.pointingLevels = pointingLevels(variable.type);
variable.uses = 0;
}
// TODO: improve the analysis precision. bitcast, for example, means we take the value, but perhaps we only use it to load/store
var inNoop = 0;
func.lines.forEach(function(line) {
walkInterdata(line, function(item) {
if (item.intertype == 'noop') inNoop++;
if (!inNoop) {
if (item.ident in func.variables) {
func.variables[item.ident].uses++;
if (item.intertype != 'load' && item.intertype != 'store') {
func.variables[item.ident].hasValueTaken = true;
}
}
}
}, function(item) {
if (item.intertype == 'noop') inNoop--;
});
});
//if (dcheck('vars')) dprint('analyzed variables: ' + dump(func.variables));
}
analyzeVariableUses();
// Decision time
for (vname in func.variables) {
var variable = func.variables[vname];
var pointedType = pointingLevels(variable.type) > 0 ? removePointing(variable.type) : null;
if (variable.origin == 'getelementptr') {
// Use our implementation that emulates pointers etc.
// TODO Can we perhaps nativize some of these? However to do so, we need to discover their
// true types; we have '?' for them now, as they cannot be discovered in the intertyper.
variable.impl = VAR_EMULATED;
} else if (variable.origin == 'funcparam') {
variable.impl = VAR_EMULATED;
} else if (variable.type == 'i64*' && USE_TYPED_ARRAYS == 2) {
variable.impl = VAR_EMULATED;
} else if (MICRO_OPTS && variable.pointingLevels === 0) {
// A simple int value, can be implemented as a native variable
variable.impl = VAR_NATIVE;
} else if (MICRO_OPTS && variable.origin === 'alloca' && !variable.hasValueTaken &&
variable.allocatedNum === 1 &&
(Runtime.isNumberType(pointedType) || Runtime.isPointerType(pointedType))) {
// A pointer to a value which is only accessible through this pointer. Basically
// a local value on the stack, which nothing fancy is done on. So we can
// optimize away the pointing altogether, and just have a native variable
variable.impl = VAR_NATIVIZED;
} else {
variable.impl = VAR_EMULATED;
}
if (dcheck('vars')) dprint('// var ' + vname + ': ' + JSON.stringify(variable));
}
});
}
// Sign analyzer
//
// Analyze our variables and detect their signs. In USE_TYPED_ARRAYS == 2,
// we can read signed or unsigned values and prevent the need for signing
// corrections. If on the other hand we are doing corrections anyhow, then
// we can skip this pass.
//
// For each variable that is the result of a Load, we look a little forward
// to see where it is used. We only care about mathops, since only they
// need signs.
//
function signalyzer() {
if (USE_TYPED_ARRAYS != 2 || CORRECT_SIGNS == 1) return;
function seekIdent(item, obj) {
if (item.ident === obj.ident) {
obj.found++;
}
}
function seekMathop(item, obj) {
if (item.intertype === 'mathop' && obj.found && !obj.decided) {
if (isUnsignedOp(item.op, item.variant)) {
obj.unsigned++;
} else {
obj.signed++;
}
}
}
item.functions.forEach(function(func) {
func.lines.forEach(function(line, i) {
if (line.intertype === 'load') {
// Floats have no concept of signedness. Mark them as 'signed', which is the default, for which we do nothing
if (line.type in Runtime.FLOAT_TYPES) {
line.unsigned = false;
return;
}
// Booleans are always unsigned
var data = func.variables[line.assignTo];
if (data.type === 'i1') {
line.unsigned = true;
return;
}
var total = data.uses;
if (total === 0) return;
var obj = { ident: line.assignTo, found: 0, unsigned: 0, signed: 0, total: total };
// in loops with phis, we can also be used *before* we are defined
var j = i-1, k = i+1;
while(1) {
assert(j >= 0 || k < func.lines.length, 'Signalyzer ran out of space to look for sign indications for line ' + line.lineNum);
if (j >= 0 && walkInterdata(func.lines[j], seekIdent, seekMathop, obj)) break;
if (k < func.lines.length && walkInterdata(func.lines[k], seekIdent, seekMathop, obj)) break;
if (obj.total && obj.found >= obj.total) break; // see comment below
j -= 1;
k += 1;
}
// unsigned+signed might be < total, since the same ident can appear multiple times in the same mathop.
// found can actually be > total, since we currently have the same ident in a GEP (see cubescript test)
// in the GEP item, and a child item (we have the ident copied onto the GEP item as a convenience).
// probably not a bug-causer, but FIXME. see also a reference to this above
// we also leave the loop above potentially early due to this. otherwise, though, we end up scanning the
// entire function in some cases which is very slow
assert(obj.found >= obj.total, 'Could not Signalyze line ' + line.lineNum);
line.unsigned = obj.unsigned > 0;
dprint('vars', 'Signalyzer: ' + line.assignTo + ' has unsigned == ' + line.unsigned + ' (line ' + line.lineNum + ')');
}
});
});
}
// Quantum fixer
//
// See settings.js for the meaning of QUANTUM_SIZE. The issue we fix here is,
// to correct the .ll assembly code so that things work with QUANTUM_SIZE=1.
//
function quantumFixer() {
if (QUANTUM_SIZE !== 1) return;
// ptrs: the indexes of parameters that are pointers, whose originalType is what we want
// bytes: the index of the 'bytes' parameter
// TODO: malloc, realloc?
var FIXABLE_CALLS = {
'memcpy': { ptrs: [0,1], bytes: 2 },
'memmove': { ptrs: [0,1], bytes: 2 },
'memset': { ptrs: [0], bytes: 2 },
'qsort': { ptrs: [0], bytes: 2 }
};
function getSize(types, type, fat) {
if (types[type]) return types[type].flatSize;
if (fat) {
Runtime.QUANTUM_SIZE = 4;
}
var ret = Runtime.getNativeTypeSize(type);
if (fat) {
Runtime.QUANTUM_SIZE = 1;
}
return ret;
}
function getFlatIndexes(types, type) {
if (types[type]) return types[type].flatIndexes;
return [0];
}
item.functions.forEach(function(func) {
function getOriginalType(param) {
function get() {
if (param.intertype === 'value' && !isNumber(param.ident)) {
if (func.variables[param.ident]) {
return func.variables[param.ident].originalType || null;
} else {
return item.globalVariables[param.ident].originalType;
}
} else if (param.intertype === 'bitcast') {
return param.params[0].type;
} else if (param.intertype === 'getelementptr') {
if (param.params[0].type[0] === '[') return param.params[0].type;
}
return null;
}
var ret = get();
if (ret && ret[0] === '[') {
var check = /^\[(\d+)\ x\ (.*)\]\*$/.exec(ret);
assert(check);
ret = check[2] + '*';
}
return ret;
}
func.lines.forEach(function(line) {
// Call
if (line.intertype === 'call') {
var funcIdent = LibraryManager.getRootIdent(line.ident.substr(1));
var fixData = FIXABLE_CALLS[funcIdent];
if (!fixData) return;
var ptrs = fixData.ptrs.map(function(ptr) { return line.params[ptr] });
var bytes = line.params[fixData.bytes].ident;
// Only consider original types. This assumes memcpy always has pointers bitcast to i8*
var originalTypes = ptrs.map(getOriginalType);
for (var i = 0; i < originalTypes.length; i++) {
if (!originalTypes[i]) return;
}
originalTypes = originalTypes.map(function(type) { return removePointing(type) });
var sizes = originalTypes.map(function(type) { return getSize(Types.types, type) });
var fatSizes = originalTypes.map(function(type) { return getSize(Types.fatTypes, type, true) });
// The sizes may not be identical, if we copy a descendant class into a parent class. We use
// the smaller size in that case. However, this may also be a bug, it is hard to tell, hence a warning
warn(dedup(sizes).length === 1, 'All sizes should probably be identical here: ' + dump(originalTypes) + ':' + dump(sizes) + ':' +
line.lineNum);
warn(dedup(fatSizes).length === 1, 'All fat sizes should probably be identical here: ' + dump(originalTypes) + ':' + dump(sizes) + ':' +
line.lineNum);
var size = Math.min.apply(null, sizes);
var fatSize = Math.min.apply(null, fatSizes);
if (isNumber(bytes)) {
// Figure out how much to copy.
var fixedBytes;
if (bytes % fatSize === 0) {
fixedBytes = size*(bytes/fatSize);
} else if (fatSize % bytes === 0 && size % (fatSize/bytes) === 0) {
// Assume this is a simple array. XXX We can be wrong though! See next TODO
fixedBytes = size/(fatSize/bytes);
} else {
// Just part of a structure. Align them to see how many fields. Err on copying more.
// TODO: properly generate a complete structure, including nesteds, and calculate on that
var flatIndexes = getFlatIndexes(Types.types, originalTypes[0]).concat(size);
var fatFlatIndexes = getFlatIndexes(Types.fatTypes, originalTypes[0]).concat(fatSize);
var index = 0;
var left = bytes;
fixedBytes = 0;
while (left > 0) {
left -= fatFlatIndexes[index+1] - fatFlatIndexes[index]; // note: we copy the alignment bytes too, which is unneeded
fixedBytes += flatIndexes[index+1] - flatIndexes[index];
}
}
line.params[fixData.bytes].ident = fixedBytes;
} else {
line.params[fixData.bytes].intertype = 'jsvalue';
// We have an assertion in library::memcpy() that this is round
line.params[fixData.bytes].ident = size + '*(' + bytes + '/' + fatSize + ')';
}
}
});
});
// 2nd part - fix hardcoded constant offsets in global constants
values(item.globalVariables).forEach(function(variable) {
function recurse(item) {
if (item.contents) {
item.contents.forEach(recurse);
} else if (item.intertype === 'getelementptr' && item.params[0].intertype === 'bitcast' && item.params[0].type === 'i8*') {
var originalType = removePointing(item.params[0].params[0].type);
var fatSize = getSize(Types.fatTypes, originalType, true);
var slimSize = getSize(Types.types, originalType, false);
assert(fatSize % slimSize === 0);
item.params.slice(1).forEach(function(param) {
if (param.intertype === 'value' && isNumber(param.ident)) {
var corrected = parseInt(param.ident)/(fatSize/slimSize);
assert(corrected % 1 === 0);
param.ident = corrected.toString();
}
});
} else if (item.params) {
item.params.forEach(recurse);
}
}
if (!variable.external && variable.value) recurse(variable.value);
});
}
function operateOnLabels(line, func) {
function process(item, id) {
['label', 'labelTrue', 'labelFalse', 'toLabel', 'unwindLabel', 'defaultLabel'].forEach(function(id) {
if (item[id]) {
func(item, id);
}
});
}
if (line.intertype in BRANCH_INVOKE) {
process(line);
} else if (line.intertype == 'switch') {
process(line);
line.switchLabels.forEach(process);
}
}
// Label analyzer
function labelAnalyzer() {
item.functions.forEach(function(func) {
func.labelsDict = {};
func.labelIds = {};
func.labelIdsInverse = {};
func.labelIdCounter = 1;
func.labels.forEach(function(label) {
if (!(label.ident in func.labelIds)) {
func.labelIds[label.ident] = func.labelIdCounter++;
func.labelIdsInverse[func.labelIdCounter-1] = label.ident;
}
});
var entryIdent = func.labels[0].ident;
// Minify label ids to numeric ids.
func.labels.forEach(function(label) {
label.ident = func.labelIds[label.ident];
label.lines.forEach(function(line) {
operateOnLabels(line, function(item, id) {
item[id] = func.labelIds[item[id]].toString(); // strings, because we will append as we process
});
});
});
func.labels.forEach(function(label) {
func.labelsDict[label.ident] = label;
});
// Correct phis
func.labels.forEach(function(label) {
label.lines.forEach(function(phi) {
if (phi.intertype == 'phi') {
for (var i = 0; i < phi.params.length; i++) {
phi.params[i].label = func.labelIds[phi.params[i].label];
if (VERBOSE && !phi.params[i].label) warn('phi refers to nonexistent label on line ' + phi.lineNum);
}
}
});
});
func.lines.forEach(function(line) {
if (line.intertype == 'indirectbr') {
func.forceEmulated = true;
}
});
function getActualLabelId(labelId) {
if (func.labelsDict[labelId]) return labelId;
// If not present, it must be a surprisingly-named entry (or undefined behavior, in which case, still ok to use the entry)
labelId = func.labelIds[entryIdent];
assert(func.labelsDict[labelId]);
return labelId;
}
// Basic longjmp support, see library.js setjmp/longjmp
var setjmp = toNiceIdent('@setjmp');
func.setjmpTable = null;
for (var i = 0; i < func.labels.length; i++) {
var label = func.labels[i];
for (var j = 0; j < label.lines.length; j++) {
var line = label.lines[j];
if ((line.intertype == 'call' || line.intertype == 'invoke') && line.ident == setjmp) {
// Add a new label
var oldLabel = label.ident;
var newLabel = func.labelIdCounter++;
if (!func.setjmpTable) func.setjmpTable = [];
func.setjmpTable.push({ oldLabel: oldLabel, newLabel: newLabel, assignTo: line.assignTo });
func.labels.splice(i+1, 0, {
intertype: 'label',
ident: newLabel,
lineNum: label.lineNum + 0.5,
lines: label.lines.slice(j+1)
});
func.labelsDict[newLabel] = func.labels[i+1];
label.lines = label.lines.slice(0, j+1);
label.lines.push({
intertype: 'branch',
label: toNiceIdent(newLabel),
lineNum: line.lineNum + 0.01, // XXX legalizing might confuse this
});
// Correct phis
func.labels.forEach(function(label) {
label.lines.forEach(function(phi) {
if (phi.intertype == 'phi') {
for (var i = 0; i < phi.params.length; i++) {
var sourceLabelId = getActualLabelId(phi.params[i].label);
if (sourceLabelId == oldLabel) {
phi.params[i].label = newLabel;
}
}
}
});
});
}
}
}
if (func.setjmpTable) {
func.forceEmulated = true;
recomputeLines(func);
}
// Properly implement phis, by pushing them back into the branch
// that leads to here. We will only have the |var| definition in this location.
// First, push phis back
func.labels.forEach(function(label) {
label.lines.forEach(function(phi) {
if (phi.intertype == 'phi') {
for (var i = 0; i < phi.params.length; i++) {
var param = phi.params[i];
if (VERBOSE && !param.label) warn('phi refers to nonexistent label on line ' + phi.lineNum);
var sourceLabelId = getActualLabelId(param.label);
if (sourceLabelId) {
var sourceLabel = func.labelsDict[sourceLabelId];
var lastLine = sourceLabel.lines.slice(-1)[0];
assert(lastLine.intertype in LLVM.PHI_REACHERS, 'Only some can lead to labels with phis:' + [func.ident, label.ident, lastLine.intertype]);
if (!lastLine.phi) {
lastLine.phi = true;
assert(!lastLine.dependent);
lastLine.dependent = {
intertype: 'phiassigns',
params: []
};
};
lastLine.dependent.params.push({
intertype: 'phiassign',
ident: phi.assignTo,
value: param.value,
targetLabel: label.ident
});
}
}
// The assign to phi is now just a var
phi.intertype = 'var';
phi.ident = phi.assignTo;
phi.assignTo = null;
}
});
});
if (func.ident in NECESSARY_BLOCKADDRS) {
Functions.blockAddresses[func.ident] = {};
for (var needed in NECESSARY_BLOCKADDRS[func.ident]) {
assert(needed in func.labelIds);
Functions.blockAddresses[func.ident][needed] = func.labelIds[needed];
}
}
});
}
// Stack analyzer - calculate the base stack usage
function stackAnalyzer() {
data.functions.forEach(function(func) {
var lines = func.labels[0].lines;
for (var i = 0; i < lines.length; i++) {
var item = lines[i];
if (!item.assignTo || item.intertype != 'alloca' || !isNumber(item.allocatedNum)) break;
item.allocatedSize = func.variables[item.assignTo].impl === VAR_EMULATED ?
calcAllocatedSize(item.allocatedType)*item.allocatedNum: 0;
if (USE_TYPED_ARRAYS === 2) {
// We need to keep the stack aligned
item.allocatedSize = Runtime.forceAlign(item.allocatedSize, Runtime.STACK_ALIGN);
}
}
var index = 0;
for (var i = 0; i < lines.length; i++) {
var item = lines[i];
if (!item.assignTo || item.intertype != 'alloca' || !isNumber(item.allocatedNum)) break;
item.allocatedIndex = index;
index += item.allocatedSize;
delete item.allocatedSize;
}
func.initialStack = index;
func.otherStackAllocations = false;
while (func.initialStack == 0) { // one-time loop with possible abort in the middle
// If there is no obvious need for stack management, perhaps we don't need it
// (we try to optimize that way with SKIP_STACK_IN_SMALL). However,
// we need to note if stack allocations other than initial allocs can happen here
// If so, we need to rewind the stack when we leave.
// By-value params are causes of additional allocas (although we could in theory make them normal allocas too)
func.params.forEach(function(param) {
if (param.byVal) {
func.otherStackAllocations = true;
}
});
if (func.otherStackAllocations) break;
// Allocas
var finishedInitial = false;
lines = func.lines; // We need to consider all the function lines now, not just the first label
for (var i = 0; i < lines.length; i++) {
var item = lines[i];
if (!finishedInitial && (!item.assignTo || item.intertype != 'alloca' || !isNumber(item.allocatedNum))) {
finishedInitial = true;
}
if (item.intertype == 'alloca' && finishedInitial) {
func.otherStackAllocations = true;
break;
}
}
if (func.otherStackAllocations) break;
// Varargs
for (var i = 0; i < lines.length; i++) {
var item = lines[i];
if (item.intertype == 'call' && isVarArgsFunctionType(item.type)) {
func.otherStackAllocations = true;
break;
}
}
if (func.otherStackAllocations) break;
break;
}
});
}
// ReLooper - reconstruct nice loops, as much as possible
// This is now done in the jsify stage, using compiled relooper2
function relooper() {
function makeBlock(labels, entries, labelsDict, forceEmulated) {
if (labels.length == 0) return null;
dprint('relooping', 'prelooping: ' + entries + ',' + labels.length + ' labels');
assert(entries && entries[0]); // need at least 1 entry
var emulated = {
type: 'emulated',
id: 'B',
labels: labels,
entries: entries.slice(0)
};
return emulated;
}
item.functions.forEach(function(func) {
dprint('relooping', "// relooping function: " + func.ident);
func.block = makeBlock(func.labels, [func.labels[0].ident], func.labelsDict, func.forceEmulated);
});
}
// main
castAway();
legalizer();
typevestigator();
analyzeTypes();
variableAnalyzer();
signalyzer();
quantumFixer();
labelAnalyzer();
stackAnalyzer();
relooper();
return item;
}
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