gvn.Analyze();
}
+ // Replace the results of check instructions with the original value, if the
+ // result is used. This is safe now, since we don't do code motion after this
+ // point. It enables better register allocation since the value produced by
+ // check instructions is really a copy of the original value.
+ graph()->ReplaceCheckedValues();
+
return graph();
}
+void HGraph::ReplaceCheckedValues() {
+ HPhase phase("Replace checked values", this);
+ for (int i = 0; i < blocks()->length(); ++i) {
+ HInstruction* instr = blocks()->at(i)->first();
+ while (instr != NULL) {
+ if (instr->IsBoundsCheck()) {
+ // Replace all uses of the checked value with the original input.
+ ASSERT(instr->UseCount() > 0);
+ instr->ReplaceAllUsesWith(HBoundsCheck::cast(instr)->index());
+ }
+ instr = instr->next();
+ }
+ }
+}
+
+
HInstruction* HGraphBuilder::AddInstruction(HInstruction* instr) {
ASSERT(current_block() != NULL);
current_block()->AddInstruction(instr);
bool is_array = (map->instance_type() == JS_ARRAY_TYPE);
HLoadElements* elements = new(zone()) HLoadElements(object);
HInstruction* length = NULL;
+ HInstruction* checked_key = NULL;
if (is_array) {
length = AddInstruction(new(zone()) HJSArrayLength(object));
- AddInstruction(new(zone()) HBoundsCheck(key, length));
+ checked_key = AddInstruction(new(zone()) HBoundsCheck(key, length));
AddInstruction(elements);
} else {
AddInstruction(elements);
length = AddInstruction(new(zone()) HFixedArrayLength(elements));
- AddInstruction(new(zone()) HBoundsCheck(key, length));
+ checked_key = AddInstruction(new(zone()) HBoundsCheck(key, length));
}
- return new(zone()) HLoadKeyedFastElement(elements, key);
+ return new(zone()) HLoadKeyedFastElement(elements, checked_key);
}
AddInstruction(elements);
HInstruction* length = new(zone()) HExternalArrayLength(elements);
AddInstruction(length);
- AddInstruction(new(zone()) HBoundsCheck(key, length));
+ HInstruction* checked_key =
+ AddInstruction(new(zone()) HBoundsCheck(key, length));
HLoadExternalArrayPointer* external_elements =
new(zone()) HLoadExternalArrayPointer(elements);
AddInstruction(external_elements);
HLoadKeyedSpecializedArrayElement* pixel_array_value =
new(zone()) HLoadKeyedSpecializedArrayElement(
- external_elements, key, expr->external_array_type());
+ external_elements, checked_key, expr->external_array_type());
return pixel_array_value;
}
} else {
length = AddInstruction(new(zone()) HFixedArrayLength(elements));
}
- AddInstruction(new(zone()) HBoundsCheck(key, length));
- return new(zone()) HStoreKeyedFastElement(elements, key, val);
+ HInstruction* checked_key =
+ AddInstruction(new(zone()) HBoundsCheck(key, length));
+ return new(zone()) HStoreKeyedFastElement(elements, checked_key, val);
}
AddInstruction(elements);
HInstruction* length = AddInstruction(
new(zone()) HExternalArrayLength(elements));
- AddInstruction(new(zone()) HBoundsCheck(key, length));
+ HInstruction* checked_key =
+ AddInstruction(new(zone()) HBoundsCheck(key, length));
HLoadExternalArrayPointer* external_elements =
new(zone()) HLoadExternalArrayPointer(elements);
AddInstruction(external_elements);
}
return new(zone()) HStoreKeyedSpecializedArrayElement(
external_elements,
- key,
+ checked_key,
val,
expr->external_array_type());
}
HInstruction* elements = AddInstruction(new(zone()) HArgumentsElements);
HInstruction* length = AddInstruction(
new(zone()) HArgumentsLength(elements));
- AddInstruction(new(zone()) HBoundsCheck(key, length));
- result = new(zone()) HAccessArgumentsAt(elements, length, key);
+ HInstruction* checked_key =
+ AddInstruction(new(zone()) HBoundsCheck(key, length));
+ result = new(zone()) HAccessArgumentsAt(elements, length, checked_key);
}
ast_context()->ReturnInstruction(result, expr->id());
return true;
AddInstruction(HCheckInstanceType::NewIsString(string));
HStringLength* length = new(zone()) HStringLength(string);
AddInstruction(length);
- AddInstruction(new(zone()) HBoundsCheck(index, length));
- return new(zone()) HStringCharCodeAt(string, index);
+ HInstruction* checked_index =
+ AddInstruction(new(zone()) HBoundsCheck(index, length));
+ return new(zone()) HStringCharCodeAt(string, checked_index);
}
--- /dev/null
+// Copyright 2011 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following
+// disclaimer in the documentation and/or other materials provided
+// with the distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived
+// from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Flags: --allow-natives-syntax
+
+gW=gH=175;
+g=[];
+
+for(var n=0; n<gW; n++){
+ var l=[];
+ for(var p=0; p<gH; p++){
+ l.push(1)
+ }
+ g.push(l)
+}
+
+function k(a,b){
+ if(a<0||b<0||a>=gW||b>=gH)
+ return 0;
+ return g[a][b];
+}
+
+function f(){
+ for(var a=[],f=0; f<gW; f++){
+ var b=[];
+ for(var h=0; h<gH; h++){
+ var e=0;
+ for(var i=-1; i<=1; i++)
+ for(var j=-1; j<=1; j++)
+ e+=k(f+i,h+j);
+ e=k(f,h)==1?1:0;
+ b.push(e)
+ }
+ a.push(b)
+ }
+}
+
+f();
+%OptimizeFunctionOnNextCall(f);
+f();
+