Commit Graph

13 Commits

Author SHA1 Message Date
Dan Gohman
572645cf84 Reapply the new LoopStrengthReduction code, with compile time and
bug fixes, and with improved heuristics for analyzing foreign-loop
addrecs.

This change also flattens IVUsers, eliminating the stride-oriented
groupings, which makes it easier to work with.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95975 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-12 10:34:29 +00:00
Dan Gohman
7979b72feb Revert LoopStrengthReduce.cpp to pre-r94061 for now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94123 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-22 00:46:49 +00:00
Dan Gohman
a10756ee65 Re-implement the main strength-reduction portion of LoopStrengthReduction.
This new version is much more aggressive about doing "full" reduction in
cases where it reduces register pressure, and also more aggressive about
rewriting induction variables to count down (or up) to zero when doing so
reduces register pressure.

It currently uses fairly simplistic algorithms for finding reuse
opportunities, but it introduces a new framework allows it to combine
multiple strategies at once to form hybrid solutions, instead of doing
all full-reduction or all base+index.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94061 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-21 02:09:26 +00:00
Evan Cheng
777c6b7caa Re-apply 85799. It turns out my code isn't buggy.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85947 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-03 21:40:02 +00:00
Evan Cheng
454ac8961b Revert 85799 for now. It might be breaking llvm-gcc driver.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85827 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-02 21:49:14 +00:00
Evan Cheng
72ed88feac Initilize the machine LICM CSE map upon the first time an instruction is hoisted to
the loop preheader. Add instructions which are already in the preheader block that
may be common expressions of those that are hoisted out. These does get a few more
instructions CSE'ed.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85799 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-02 08:09:49 +00:00
Dan Gohman
36a0947820 Eliminate more uses of llvm-as and llvm-dis.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81290 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-08 23:54:48 +00:00
Dan Gohman
ae3a0be92e Split the Add, Sub, and Mul instruction opcodes into separate
integer and floating-point opcodes, introducing
FAdd, FSub, and FMul.

For now, the AsmParser, BitcodeReader, and IRBuilder all preserve
backwards compatability, and the Core LLVM APIs preserve backwards
compatibility for IR producers. Most front-ends won't need to change
immediately.

This implements the first step of the plan outlined here:
http://nondot.org/sabre/LLVMNotes/IntegerOverflow.txt


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72897 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-04 22:49:04 +00:00
Dale Johannesen
c1acc3f764 Reverse a loop that is counting up to a maximum to
count down to 0 instead, under very restricted
circumstances.  Adjust 4 testcases in which this
optimization fires.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71439 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-11 17:15:42 +00:00
Owen Anderson
d6db225800 Eliminate another use of -disable-correct-folding.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54356 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-05 18:03:01 +00:00
Owen Anderson
2b85dc3544 Update these tests to work by disabling the new correct CFG generation. This flag should ONLY be used to for tests like these.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54334 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-04 23:55:29 +00:00
Evan Cheng
601ca4b434 Enable two-address remat by default.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52701 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-25 01:16:38 +00:00
Evan Cheng
cddbb83ea8 Do not fold reload into an instruction with multiple uses. It issues one extra load.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44467 91177308-0d34-0410-b5e6-96231b3b80d8
2007-11-30 21:23:43 +00:00