[Open64-devel] WHIRL question
(forwarding this question) This code j = --i + i--; Is transformed into this (pseudo)WHIRL: STID(i) - ADD - LDID(i) ; this is the side \ INTCONST(-1); effect of the --i expression STID(preg_I4) - LDID(i) ; storage of the previous ; i value STID(i) - ADD - LDID(i) ; this is the side \ INTCONST(-1); effect of the i-- expression STID(j) - ADD - LDID(preg_I4) ; the actual \ LDID(i) ; j = expression what is the advantage of this WHIRL instead of STID(i) - ADD - LDID(i) ; this is the side \ INTCONST(-1); effect of the --i expression STID(j) - ADD - LDID(i) ; the actual \ LDID(i) ; j = expression STID(i) - ADD - LDID(i) ; this is the side \ INTCONST(-1); effect of the --i expression the first version just uses one more WHIRL node and one more variable. why is it used? is it because it's easier to rewrite C - WHIRL in that way? -- Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing. http://p.sf.net/sfu/novell-sfdev2dev ___ Open64-devel mailing list Open64-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/open64-devel
Re: [Open64-devel] WHIRL question
I suspect that the translation is done in a way that that ensures correctness. The temp is not needed in your example, but it is needed for: j = i-- + i-- Doug -Original Message- From: C. Bergström [mailto:cbergst...@pathscale.com] Sent: Wednesday, September 29, 2010 7:15 AM To: open64-devel Subject: [Open64-devel] WHIRL question (forwarding this question) This code j = --i + i--; Is transformed into this (pseudo)WHIRL: STID(i) - ADD - LDID(i) ; this is the side \ INTCONST(-1); effect of the --i expression STID(preg_I4) - LDID(i) ; storage of the previous ; i value STID(i) - ADD - LDID(i) ; this is the side \ INTCONST(-1); effect of the i-- expression STID(j) - ADD - LDID(preg_I4) ; the actual \ LDID(i) ; j = expression what is the advantage of this WHIRL instead of STID(i) - ADD - LDID(i) ; this is the side \ INTCONST(-1); effect of the --i expression STID(j) - ADD - LDID(i) ; the actual \ LDID(i) ; j = expression STID(i) - ADD - LDID(i) ; this is the side \ INTCONST(-1); effect of the --i expression the first version just uses one more WHIRL node and one more variable. why is it used? is it because it's easier to rewrite C - WHIRL in that way? --- --- Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing. http://p.sf.net/sfu/novell-sfdev2dev ___ Open64-devel mailing list Open64-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/open64-devel -- Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing. http://p.sf.net/sfu/novell-sfdev2dev ___ Open64-devel mailing list Open64-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/open64-devel
Re: [Open64-devel] WHIRL question
I think it might have been done to handle the case where i is volatile. It might also be needed for code dealing with auto decrement coupled with pointer dereferencing and the computing of pointer involves an expression having side effects. Murthy -Original Message- From: Gilmore, Doug [mailto:doug.gilm...@amd.com] Sent: Wednesday, September 29, 2010 10:39 AM To: C. Bergström; open64-devel Subject: Re: [Open64-devel] WHIRL question I suspect that the translation is done in a way that that ensures correctness. The temp is not needed in your example, but it is needed for: j = i-- + i-- Doug -Original Message- From: C. Bergström [mailto:cbergst...@pathscale.com] Sent: Wednesday, September 29, 2010 7:15 AM To: open64-devel Subject: [Open64-devel] WHIRL question (forwarding this question) This code j = --i + i--; Is transformed into this (pseudo)WHIRL: STID(i) - ADD - LDID(i) ; this is the side \ INTCONST(-1); effect of the --i expression STID(preg_I4) - LDID(i) ; storage of the previous ; i value STID(i) - ADD - LDID(i) ; this is the side \ INTCONST(-1); effect of the i-- expression STID(j) - ADD - LDID(preg_I4) ; the actual \ LDID(i) ; j = expression what is the advantage of this WHIRL instead of STID(i) - ADD - LDID(i) ; this is the side \ INTCONST(-1); effect of the --i expression STID(j) - ADD - LDID(i) ; the actual \ LDID(i) ; j = expression STID(i) - ADD - LDID(i) ; this is the side \ INTCONST(-1); effect of the --i expression the first version just uses one more WHIRL node and one more variable. why is it used? is it because it's easier to rewrite C - WHIRL in that way? --- --- Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing. http://p.sf.net/sfu/novell-sfdev2dev ___ Open64-devel mailing list Open64-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/open64-devel -- Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing. http://p.sf.net/sfu/novell-sfdev2dev ___ Open64-devel mailing list Open64-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/open64-devel -- Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing. http://p.sf.net/sfu/novell-sfdev2dev ___ Open64-devel mailing list Open64-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/open64-devel
