forked from OSchip/llvm-project
![]() In r263618, JumpThreading learned to look trough simple cast instructions, but only if the source of those cast instructions was a phi/cmp i1 (in an effort to limit compile time effects). I think this condition is too restrictive. For switches with limited value range, InstCombine will readily introduce an extra trunc instruction to a smaller integer type (e.g. from i8 to i2), leaving us in the somewhat perverse situation that jump-threading would work before running instcombine, but not after. Since instcombine produces this pattern, I think we need to consider it canonical and support it in JumpThreading. In general, for limiting recursion, I think the existing restriction to phi and cmp nodes should be sufficient to avoid looking through unprofitable chains of instructions. Patch by Keno Fischer! Differential Revision: https://reviews.llvm.org/D42262 llvm-svn: 327150 |
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2008-11-27-EntryMunge.ll | ||
2010-08-26-and.ll | ||
2011-04-02-SimplifyDeadBlock.ll | ||
2011-04-14-InfLoop.ll | ||
2012-07-19-NoSuccessorIndirectBr.ll | ||
and-and-cond.ll | ||
and-cond.ll | ||
assume-edge-dom.ll | ||
assume.ll | ||
basic.ll | ||
branch-no-const.ll | ||
compare.ll | ||
conservative-lvi.ll | ||
crash.ll | ||
ddt-crash.ll | ||
ddt-crash2.ll | ||
ddt-crash3.ll | ||
ddt-crash4.ll | ||
degenerate-phi.ll | ||
fold-not-thread.ll | ||
guards.ll | ||
implied-cond.ll | ||
indirectbr.ll | ||
induction.ll | ||
landing-pad.ll | ||
lvi-load.ll | ||
lvi-tristate.ll | ||
no-irreducible-loops.ll | ||
or-undef.ll | ||
phi-eq.ll | ||
phi-known.ll | ||
pr9331.ll | ||
pr15851_hang.ll | ||
pr22086.ll | ||
pr26096.ll | ||
pr27840.ll | ||
pr33605.ll | ||
pr33917.ll | ||
pr36133.ll | ||
range-compare.ll | ||
select.ll | ||
static-profile.ll | ||
thread-cmp.ll | ||
thread-loads.ll | ||
threading_prof1.ll | ||
threading_prof2.ll | ||
update-edge-weight.ll |