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* [Bug tree-optimization/21596] New: [4.0/4.1 Regression] extra temporaries when using global register variables @ 2005-05-15 23:45 rth at gcc dot gnu dot org 2005-05-15 23:57 ` [Bug tree-optimization/21596] " pinskia at gcc dot gnu dot org ` (2 more replies) 0 siblings, 3 replies; 4+ messages in thread From: rth at gcc dot gnu dot org @ 2005-05-15 23:45 UTC (permalink / raw) To: gcc-bugs register int *reg __asm__("%edi"); int test () { return *--reg <= 0; } With -O2 -fomit-frame-pointer, 4.0, movl %edi, %eax leal -4(%edi), %edi movl -4(%eax), %eax testl %eax, %eax With 3.4, subl $4, %edi cmpl $0, (%edi) The problem appears to begin at the tree level, with extra temporaries: reg.0 = reg; reg.2 = reg.0 - 4B; reg = reg.2; return *reg.2 <= 0; We do consider hard register variables not is_gimple_reg, due to needing to V_MAY_DEF them at call sites. It would be nice if we could eliminate these temporaries during TER, or something. -- Summary: [4.0/4.1 Regression] extra temporaries when using global register variables Product: gcc Version: 4.0.0 Status: UNCONFIRMED Severity: normal Priority: P2 Component: tree-optimization AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: rth at gcc dot gnu dot org CC: amacleod at redhat dot com,gcc-bugs at gcc dot gnu dot org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21596 ^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug tree-optimization/21596] [4.0/4.1 Regression] extra temporaries when using global register variables 2005-05-15 23:45 [Bug tree-optimization/21596] New: [4.0/4.1 Regression] extra temporaries when using global register variables rth at gcc dot gnu dot org @ 2005-05-15 23:57 ` pinskia at gcc dot gnu dot org 2005-07-08 1:42 ` mmitchel at gcc dot gnu dot org 2005-09-27 16:23 ` mmitchel at gcc dot gnu dot org 2 siblings, 0 replies; 4+ messages in thread From: pinskia at gcc dot gnu dot org @ 2005-05-15 23:57 UTC (permalink / raw) To: gcc-bugs ------- Additional Comments From pinskia at gcc dot gnu dot org 2005-05-15 23:57 ------- Confirmed. -- What |Removed |Added ---------------------------------------------------------------------------- CC| |pinskia at gcc dot gnu dot | |org Status|UNCONFIRMED |NEW Ever Confirmed| |1 Keywords| |missed-optimization Last reconfirmed|0000-00-00 00:00:00 |2005-05-15 23:57:38 date| | Target Milestone|--- |4.0.1 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21596 ^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug tree-optimization/21596] [4.0/4.1 Regression] extra temporaries when using global register variables 2005-05-15 23:45 [Bug tree-optimization/21596] New: [4.0/4.1 Regression] extra temporaries when using global register variables rth at gcc dot gnu dot org 2005-05-15 23:57 ` [Bug tree-optimization/21596] " pinskia at gcc dot gnu dot org @ 2005-07-08 1:42 ` mmitchel at gcc dot gnu dot org 2005-09-27 16:23 ` mmitchel at gcc dot gnu dot org 2 siblings, 0 replies; 4+ messages in thread From: mmitchel at gcc dot gnu dot org @ 2005-07-08 1:42 UTC (permalink / raw) To: gcc-bugs -- What |Removed |Added ---------------------------------------------------------------------------- Target Milestone|4.0.1 |4.0.2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21596 ^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug tree-optimization/21596] [4.0/4.1 Regression] extra temporaries when using global register variables 2005-05-15 23:45 [Bug tree-optimization/21596] New: [4.0/4.1 Regression] extra temporaries when using global register variables rth at gcc dot gnu dot org 2005-05-15 23:57 ` [Bug tree-optimization/21596] " pinskia at gcc dot gnu dot org 2005-07-08 1:42 ` mmitchel at gcc dot gnu dot org @ 2005-09-27 16:23 ` mmitchel at gcc dot gnu dot org 2 siblings, 0 replies; 4+ messages in thread From: mmitchel at gcc dot gnu dot org @ 2005-09-27 16:23 UTC (permalink / raw) To: gcc-bugs -- What |Removed |Added ---------------------------------------------------------------------------- Target Milestone|4.0.2 |4.0.3 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21596 ^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2005-09-27 16:22 UTC | newest] Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2005-05-15 23:45 [Bug tree-optimization/21596] New: [4.0/4.1 Regression] extra temporaries when using global register variables rth at gcc dot gnu dot org 2005-05-15 23:57 ` [Bug tree-optimization/21596] " pinskia at gcc dot gnu dot org 2005-07-08 1:42 ` mmitchel at gcc dot gnu dot org 2005-09-27 16:23 ` mmitchel at gcc dot gnu dot org
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