Title: [147669] trunk/Source/_javascript_Core
- Revision
- 147669
- Author
- [email protected]
- Date
- 2013-04-04 14:16:43 -0700 (Thu, 04 Apr 2013)
Log Message
Removed a defunct comment
https://bugs.webkit.org/show_bug.cgi?id=113948
Reviewed by Oliver Hunt.
This is also a convenient way to test the EWS.
* bytecompiler/BytecodeGenerator.cpp:
(JSC):
Modified Paths
Diff
Modified: trunk/Source/_javascript_Core/ChangeLog (147668 => 147669)
--- trunk/Source/_javascript_Core/ChangeLog 2013-04-04 21:08:08 UTC (rev 147668)
+++ trunk/Source/_javascript_Core/ChangeLog 2013-04-04 21:16:43 UTC (rev 147669)
@@ -1,3 +1,15 @@
+2013-04-04 Geoffrey Garen <[email protected]>
+
+ Removed a defunct comment
+ https://bugs.webkit.org/show_bug.cgi?id=113948
+
+ Reviewed by Oliver Hunt.
+
+ This is also a convenient way to test the EWS.
+
+ * bytecompiler/BytecodeGenerator.cpp:
+ (JSC):
+
2013-04-04 Martin Robinson <[email protected]>
[GTK] Remove the gyp build
Modified: trunk/Source/_javascript_Core/bytecompiler/BytecodeGenerator.cpp (147668 => 147669)
--- trunk/Source/_javascript_Core/bytecompiler/BytecodeGenerator.cpp 2013-04-04 21:08:08 UTC (rev 147668)
+++ trunk/Source/_javascript_Core/bytecompiler/BytecodeGenerator.cpp 2013-04-04 21:16:43 UTC (rev 147669)
@@ -46,81 +46,6 @@
namespace JSC {
-/*
- The layout of a register frame looks like this:
-
- For
-
- function f(x, y) {
- var v1;
- function g() { }
- var v2;
- return (x) * (y);
- }
-
- assuming (x) and (y) generated temporaries t1 and t2, you would have
-
- ------------------------------------
- | x | y | g | v2 | v1 | t1 | t2 | <-- value held
- ------------------------------------
- | -5 | -4 | -3 | -2 | -1 | +0 | +1 | <-- register index
- ------------------------------------
- | params->|<-locals | temps->
-
- Because temporary registers are allocated in a stack-like fashion, we
- can reclaim them with a simple popping algorithm. The same goes for labels.
- (We never reclaim parameter or local registers, because parameters and
- locals are DontDelete.)
-
- The register layout before a function call looks like this:
-
- For
-
- function f(x, y)
- {
- }
-
- f(1);
-
- > <------------------------------
- < > reserved: call frame | 1 | <-- value held
- > >snip< <------------------------------
- < > +0 | +1 | +2 | +3 | +4 | +5 | <-- register index
- > <------------------------------
- | params->|<-locals | temps->
-
- The call instruction fills in the "call frame" registers. It also pads
- missing arguments at the end of the call:
-
- > <-----------------------------------
- < > reserved: call frame | 1 | ? | <-- value held ("?" stands for "undefined")
- > >snip< <-----------------------------------
- < > +0 | +1 | +2 | +3 | +4 | +5 | +6 | <-- register index
- > <-----------------------------------
- | params->|<-locals | temps->
-
- After filling in missing arguments, the call instruction sets up the new
- stack frame to overlap the end of the old stack frame:
-
- |----------------------------------> <
- | reserved: call frame | 1 | ? < > <-- value held ("?" stands for "undefined")
- |----------------------------------> >snip< <
- | -7 | -6 | -5 | -4 | -3 | -2 | -1 < > <-- register index
- |----------------------------------> <
- | | params->|<-locals | temps->
-
- That way, arguments are "copied" into the callee's stack frame for free.
-
- If the caller supplies too many arguments, this trick doesn't work. The
- extra arguments protrude into space reserved for locals and temporaries.
- In that case, the call instruction makes a real copy of the call frame header,
- along with just the arguments expected by the callee, leaving the original
- call frame header and arguments behind. (The call instruction can't just discard
- extra arguments, because the "arguments" object may access them later.)
- This copying strategy ensures that all named values will be at the indices
- expected by the callee.
-*/
-
void Label::setLocation(unsigned location)
{
m_location = location;
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