Linux kernel block sha1 code on powerpc64 has many redundant clrldi
instructions, significantly slowing execution time. Current gcc seems to
generate more of these than 3.4.5 which is in turn worse than 3.3.
Breakdown of clrldi insns
- 140 redundant clrldi on rotate insn output
- 79 other redundant clrldi
- 11 useful
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Summary: redundant ZERO_EXTENDs
Product: gcc
Version: 4.5.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: amodra at bigpond dot net dot au
GCC target triplet: powerpc64-linux
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41081
