llvm-project/llvm/lib/Transforms
Duncan Sands 8fb2c3827c At -O123 the early-cse pass is run before instcombine has run. According to my
auto-simplier the transform most missed by early-cse is (zext X) != 0 -> X != 0.
This patch adds this transform and some related logic to InstructionSimplify
and removes some of the logic from instcombine (unfortunately not all because
there are several situations in which instcombine can improve things by making
new instructions, whereas instsimplify is not allowed to do this).  At -O2 this
often results in more than 15% more simplifications by early-cse, and results in
hundreds of lines of bitcode being eliminated from the testsuite.  I did see some
small negative effects in the testsuite, for example a few additional instructions
in three programs.  One program, 483.xalancbmk, got an additional 35 instructions,
which seems to be due to a function getting an additional instruction and then
being inlined all over the place.

llvm-svn: 123911
2011-01-20 13:21:55 +00:00
..
Hello Since the Hello pass is built as a loadable dynamic library, don't try to convert it to new-style registration yet. 2010-10-07 00:31:16 +00:00
IPO Add unnamed_addr when we can show that address of a global is not used. 2011-01-19 16:32:21 +00:00
InstCombine At -O123 the early-cse pass is run before instcombine has run. According to my 2011-01-20 13:21:55 +00:00
Instrumentation Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which 2010-10-19 17:21:58 +00:00
Scalar fix rdar://8878965, a regression I introduced with the recent 2011-01-18 20:53:04 +00:00
Utils Convert a std::map to a DenseMap for another 1.7% speedup on -scalarrepl. 2011-01-18 04:50:38 +00:00
Makefile Revert r100896 and around - this breaks the only mingw32 buildbot we have. 2010-04-15 19:51:42 +00:00