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</o:shapelayout></xml><![endif]--></head><body lang=DE link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Hi,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Theoretically, both lines could indeed use the same local. However, omitting the field read is tough as it would require an analysis to detect that the field cannot be changed in the meantime. This would be possible, but it is not trivial if you have non-trivial code.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>In general, feel free to contribute simplifying transformers to the Soot project.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Best regards,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> Steven<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>Von:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> soot-list-bounces@CS.McGill.CA [mailto:soot-list-bounces@CS.McGill.CA] <b>Im Auftrag von </b>flanker017<br><b>Gesendet:</b> Mittwoch, 6. Mai 2015 15:27<br><b>An:</b> soot-list@CS.McGill.CA<br><b>Betreff:</b> [Soot-list] A question on Jimple generation<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Hi all: <o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I have a question on local allocation in jimple body generation, hope someone could kindly shed some light on this.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>For the following source code:<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>class TestActivity{<o:p></o:p></p></div><div><div><p class=MsoNormal> Intent intent;<o:p></o:p></p></div><div><p class=MsoNormal> public void test7()<o:p></o:p></p></div><div><p class=MsoNormal> {<o:p></o:p></p></div><div><p class=MsoNormal> intent = new Intent();<o:p></o:p></p></div><div><p class=MsoNormal> intent.setClass(this, TestActivity.class);<o:p></o:p></p></div><div><p class=MsoNormal> startActivity(intent);<o:p></o:p></p></div><div><p class=MsoNormal> }<o:p></o:p></p></div></div><div><p class=MsoNormal>}<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>The following jimple is generated:<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><div><p class=MsoNormal> public void test7()<o:p></o:p></p></div><div><p class=MsoNormal> {<o:p></o:p></p></div><div><p class=MsoNormal> TestActivity r0;<o:p></o:p></p></div><div><p class=MsoNormal> android.content.Intent $r1, $r2, $r3;<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal> r0 := @this: TestActivity;<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal> $r1 = new android.content.Intent;<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal> specialinvoke $r1.<android.content.Intent: void <init>()>();<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal> r0.<TestActivity: android.content.Intent intent> = $r1;<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal> $r2 = r0.<TestActivity: android.content.Intent intent>; //line 7<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal> virtualinvoke $r2.<android.content.Intent: void setClass(android.content.Context,java.lang.Class)>(r0, class "TestActivity"); //line 8<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal> $r3 = r0.<TestActivity: android.content.Intent intent>; //line9<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal> virtualinvoke r0.<TestActivity: void startActivity(android.content.Intent)>($r3); //line 10<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal> return;<o:p></o:p></p></div><div><p class=MsoNormal> }<o:p></o:p></p></div></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Why can't line9 and line7 use the same local $r2, but use two locals $r3 and $r2? Aren't them identical?<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>If only on local is used, line9 can be omitted and line10 will be virtualinvoke r0.<TestActivity: void startActivity(android.content.Intent)>($r2); <o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Thanks for any help on this question!<o:p></o:p></p></div></div></div></body></html>