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Merged
kripken merged 7 commits into from
Apr 30, 2019
Merged

wasm2js: optimize away casts going into a suitable store #2069

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b20cc12
optimize casts going into a store
kripken Apr 29, 2019
0c5cbfa
more
kripken Apr 29, 2019
69526d1
todo
kripken Apr 29, 2019
02a85ba
Merge remote-tracking branch 'origin/master' into wasm2js4
kripken Apr 30, 2019
3c63f36
format
kripken Apr 30, 2019
25d8848
format
kripken Apr 30, 2019
1581d57
Merge remote-tracking branch 'origin/master' into wasm2js4
kripken Apr 30, 2019
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106 changes: 97 additions & 9 deletions src/tools/wasm2js.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -129,7 +129,7 @@ static void traversePost(Ref node, std::function<void(Ref)> visit) {
}

static void optimizeJS(Ref ast) {
// helpers
// Helpers

auto isOrZero = [](Ref node) {
return node->isArray() && !node->empty() && node[0] == BINARY &&
Expand All @@ -141,6 +141,11 @@ static void optimizeJS(Ref ast) {
node[1] == PLUS;
};

auto isFround = [](Ref node) {
return node->isArray() && !node->empty() && node[0] == cashew::CALL &&
node[1] == MATH_FROUND;
};

auto isBitwise = [](Ref node) {
if (node->isArray() && !node->empty() && node[0] == BINARY) {
auto op = node[1];
Expand All @@ -150,6 +155,60 @@ static void optimizeJS(Ref ast) {
return false;
};

auto isConstantAnd = [](Ref node, int num) {
return node->isArray() && !node->empty() && node[0] == BINARY &&
node[1] == AND && node[3]->isNumber() && node[3]->getNumber() == num;
};

auto removeOrZero = [&](Ref node) {
while (isOrZero(node)) {
node = node[2];
}
return node;
};

auto removePlus = [&](Ref node) {
while (isPlus(node)) {
node = node[2];
}
return node;
};

auto removePlusAndFround = [&](Ref node) {
while (1) {
if (isFround(node)) {
node = node[2][0];
} else if (isPlus(node)) {
node = node[2];
} else {
break;
}
}
return node;
};

auto getHeapFromAccess = [](Ref node) { return node[1]->getIString(); };

auto isIntegerHeap = [](IString heap) {
return heap == HEAP8 || heap == HEAPU8 || heap == HEAP16 ||
heap == HEAPU16 || heap == HEAP32 || heap == HEAPU32;
};

auto isFloatHeap = [](IString heap) {
return heap == HEAPF32 || heap == HEAPF64;
};

auto isHeapAccess = [&](Ref node) {
if (node->isArray() && !node->empty() && node[0] == SUB &&
node[1]->isString()) {
auto heap = getHeapFromAccess(node);
return isIntegerHeap(heap) || isFloatHeap(heap);
}
return false;
};

// Optimizations

// x >> 0 => x | 0
traversePost(ast, [](Ref node) {
if (node->isArray() && !node->empty() && node[0] == BINARY &&
Expand All @@ -175,17 +234,46 @@ static void optimizeJS(Ref ast) {
}
// x | 0 going into a bitwise op => skip the | 0
else if (isBitwise(node)) {
while (isOrZero(node[2])) {
node[2] = node[2][2];
}
while (isOrZero(node[3])) {
node[3] = node[3][2];
}
node[2] = removeOrZero(node[2]);
node[3] = removeOrZero(node[3]);
}
// +(+x) => +x
else if (isPlus(node)) {
while (isPlus(node[2])) {
node[2] = node[2][2];
node[2] = removePlus(node[2]);
}
// +(+x) => +x
else if (isFround(node)) {
node[2] = removePlusAndFround(node[2]);
}
// Assignment into a heap coerces.
else if (node->isAssign()) {
auto assign = node->asAssign();
auto target = assign->target();
if (isHeapAccess(target)) {
auto heap = getHeapFromAccess(target);
if (isIntegerHeap(heap)) {
if (heap == HEAP8 || heap == HEAPU8) {
while (isOrZero(assign->value()) ||
isConstantAnd(assign->value(), 255)) {
assign->value() = assign->value()[2];
}
} else if (heap == HEAP16 || heap == HEAPU16) {
while (isOrZero(assign->value()) ||
isConstantAnd(assign->value(), 65535)) {
assign->value() = assign->value()[2];
}
} else {
assert(heap == HEAP32 || heap == HEAPU32);
assign->value() = removeOrZero(assign->value());
}
} else {
assert(isFloatHeap(heap));
if (heap == HEAPF32) {
assign->value() = removePlusAndFround(assign->value());
} else {
assign->value() = removePlus(assign->value());
}
}
}
}
});
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5 changes: 5 additions & 0 deletions test/wasm2js/emscripten.2asm.js
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Original file line number Diff line number Diff line change
Expand Up @@ -48,6 +48,11 @@ function asmFunc(global, env, buffer) {
HEAP8[128 | 0];
HEAPU16[128 >> 1];
HEAP16[128 >> 1];
HEAP32[16 >> 2] = 1 + 2;
HEAPF32[16 >> 2] = Math_fround(3.0) + Math_fround(4.0);
HEAPF64[16 >> 3] = 5.0 + 6.0;
HEAP8[16 | 0] = 7 + 8;
HEAP16[16 >> 1] = 9 + 10;
}

function __growWasmMemory($0) {
Expand Down
20 changes: 20 additions & 0 deletions test/wasm2js/emscripten.wast
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Original file line number Diff line number Diff line change
Expand Up @@ -52,6 +52,26 @@
(i32.const 128)
)
)
(i32.store
(i32.const 16)
(i32.add (i32.const 1) (i32.const 2))
)
(f32.store
(i32.const 16)
(f32.add (f32.const 3) (f32.const 4))
)
(f64.store
(i32.const 16)
(f64.add (f64.const 5) (f64.const 6))
)
(i32.store8
(i32.const 16)
(i32.add (i32.const 7) (i32.const 8))
)
(i32.store16
(i32.const 16)
(i32.add (i32.const 9) (i32.const 10))
)
)
(func $__growWasmMemory (param $0 i32) (result i32)
(grow_memory
Expand Down
12 changes: 6 additions & 6 deletions test/wasm2js/unaligned.2asm.js
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Original file line number Diff line number Diff line change
Expand Up @@ -84,28 +84,28 @@ function asmFunc(global, env, buffer) {

function $4() {
var wasm2js_i32$0 = 0, wasm2js_i32$1 = 0;
(wasm2js_i32$0 = 0, wasm2js_i32$1 = 0), ((HEAP8[wasm2js_i32$0 | 0] = wasm2js_i32$1 & 255, HEAP8[wasm2js_i32$0 + 1 | 0] = wasm2js_i32$1 >>> 8 & 255), HEAP8[wasm2js_i32$0 + 2 | 0] = wasm2js_i32$1 >>> 16 & 255), HEAP8[wasm2js_i32$0 + 3 | 0] = wasm2js_i32$1 >>> 24 & 255;
(wasm2js_i32$0 = 0, wasm2js_i32$1 = 0), ((HEAP8[wasm2js_i32$0 | 0] = wasm2js_i32$1, HEAP8[wasm2js_i32$0 + 1 | 0] = wasm2js_i32$1 >>> 8), HEAP8[wasm2js_i32$0 + 2 | 0] = wasm2js_i32$1 >>> 16), HEAP8[wasm2js_i32$0 + 3 | 0] = wasm2js_i32$1 >>> 24;
}

function $5() {
var i64toi32_i32$1 = 0, wasm2js_i32$0 = 0, wasm2js_i32$1 = 0;
i64toi32_i32$1 = 0;
(wasm2js_i32$0 = i64toi32_i32$1, wasm2js_i32$1 = 0), ((HEAP8[wasm2js_i32$0 | 0] = wasm2js_i32$1 & 255, HEAP8[wasm2js_i32$0 + 1 | 0] = wasm2js_i32$1 >>> 8 & 255), HEAP8[wasm2js_i32$0 + 2 | 0] = wasm2js_i32$1 >>> 16 & 255), HEAP8[wasm2js_i32$0 + 3 | 0] = wasm2js_i32$1 >>> 24 & 255;
(wasm2js_i32$0 = i64toi32_i32$1, wasm2js_i32$1 = 0), ((HEAP8[wasm2js_i32$0 + 4 | 0] = wasm2js_i32$1 & 255, HEAP8[wasm2js_i32$0 + 5 | 0] = wasm2js_i32$1 >>> 8 & 255), HEAP8[wasm2js_i32$0 + 6 | 0] = wasm2js_i32$1 >>> 16 & 255), HEAP8[wasm2js_i32$0 + 7 | 0] = wasm2js_i32$1 >>> 24 & 255;
(wasm2js_i32$0 = i64toi32_i32$1, wasm2js_i32$1 = 0), ((HEAP8[wasm2js_i32$0 | 0] = wasm2js_i32$1, HEAP8[wasm2js_i32$0 + 1 | 0] = wasm2js_i32$1 >>> 8), HEAP8[wasm2js_i32$0 + 2 | 0] = wasm2js_i32$1 >>> 16), HEAP8[wasm2js_i32$0 + 3 | 0] = wasm2js_i32$1 >>> 24;
(wasm2js_i32$0 = i64toi32_i32$1, wasm2js_i32$1 = 0), ((HEAP8[wasm2js_i32$0 + 4 | 0] = wasm2js_i32$1, HEAP8[wasm2js_i32$0 + 5 | 0] = wasm2js_i32$1 >>> 8), HEAP8[wasm2js_i32$0 + 6 | 0] = wasm2js_i32$1 >>> 16), HEAP8[wasm2js_i32$0 + 7 | 0] = wasm2js_i32$1 >>> 24;
}

function $6() {
var wasm2js_i32$0 = 0, wasm2js_i32$1 = 0;
(wasm2js_i32$0 = 0, wasm2js_i32$1 = (wasm2js_scratch_store_f32(Math_fround(0.0)), wasm2js_scratch_load_i32(0))), ((HEAP8[wasm2js_i32$0 | 0] = wasm2js_i32$1 & 255, HEAP8[wasm2js_i32$0 + 1 | 0] = wasm2js_i32$1 >>> 8 & 255), HEAP8[wasm2js_i32$0 + 2 | 0] = wasm2js_i32$1 >>> 16 & 255), HEAP8[wasm2js_i32$0 + 3 | 0] = wasm2js_i32$1 >>> 24 & 255;
(wasm2js_i32$0 = 0, wasm2js_i32$1 = (wasm2js_scratch_store_f32(Math_fround(0.0)), wasm2js_scratch_load_i32(0))), ((HEAP8[wasm2js_i32$0 | 0] = wasm2js_i32$1, HEAP8[wasm2js_i32$0 + 1 | 0] = wasm2js_i32$1 >>> 8), HEAP8[wasm2js_i32$0 + 2 | 0] = wasm2js_i32$1 >>> 16), HEAP8[wasm2js_i32$0 + 3 | 0] = wasm2js_i32$1 >>> 24;
}

function $7() {
var i64toi32_i32$1 = 0, i64toi32_i32$0 = 0, wasm2js_i32$0 = 0, wasm2js_i32$1 = 0;
wasm2js_scratch_store_f64(0.0);
i64toi32_i32$0 = wasm2js_scratch_load_i32(1 | 0) | 0;
i64toi32_i32$1 = 0;
(wasm2js_i32$0 = i64toi32_i32$1, wasm2js_i32$1 = wasm2js_scratch_load_i32(0 | 0) | 0), ((HEAP8[wasm2js_i32$0 | 0] = wasm2js_i32$1 & 255, HEAP8[wasm2js_i32$0 + 1 | 0] = wasm2js_i32$1 >>> 8 & 255), HEAP8[wasm2js_i32$0 + 2 | 0] = wasm2js_i32$1 >>> 16 & 255), HEAP8[wasm2js_i32$0 + 3 | 0] = wasm2js_i32$1 >>> 24 & 255;
(wasm2js_i32$0 = i64toi32_i32$1, wasm2js_i32$1 = i64toi32_i32$0), ((HEAP8[wasm2js_i32$0 + 4 | 0] = wasm2js_i32$1 & 255, HEAP8[wasm2js_i32$0 + 5 | 0] = wasm2js_i32$1 >>> 8 & 255), HEAP8[wasm2js_i32$0 + 6 | 0] = wasm2js_i32$1 >>> 16 & 255), HEAP8[wasm2js_i32$0 + 7 | 0] = wasm2js_i32$1 >>> 24 & 255;
(wasm2js_i32$0 = i64toi32_i32$1, wasm2js_i32$1 = wasm2js_scratch_load_i32(0 | 0) | 0), ((HEAP8[wasm2js_i32$0 | 0] = wasm2js_i32$1, HEAP8[wasm2js_i32$0 + 1 | 0] = wasm2js_i32$1 >>> 8), HEAP8[wasm2js_i32$0 + 2 | 0] = wasm2js_i32$1 >>> 16), HEAP8[wasm2js_i32$0 + 3 | 0] = wasm2js_i32$1 >>> 24;
(wasm2js_i32$0 = i64toi32_i32$1, wasm2js_i32$1 = i64toi32_i32$0), ((HEAP8[wasm2js_i32$0 + 4 | 0] = wasm2js_i32$1, HEAP8[wasm2js_i32$0 + 5 | 0] = wasm2js_i32$1 >>> 8), HEAP8[wasm2js_i32$0 + 6 | 0] = wasm2js_i32$1 >>> 16), HEAP8[wasm2js_i32$0 + 7 | 0] = wasm2js_i32$1 >>> 24;
}

function legalstub$1() {
Expand Down