Commit Graph

12 Commits

Author SHA1 Message Date
Jakob Stoklund Olesen bd09d45489 Fix register-dependent X86 tests.
llvm-svn: 128867
2011-04-05 00:32:44 +00:00
Dan Gohman 2850b41412 Revert r97580; that's not the right way to fix this.
llvm-svn: 97639
2010-03-03 04:36:42 +00:00
Dan Gohman d55f574589 When expanding an expression such as (A + B + C + D), sort the operands
by loop depth and emit loop-invariant subexpressions outside of loops.
This speeds up MultiSource/Applications/viterbi and others.

llvm-svn: 97580
2010-03-02 19:32:21 +00:00
Dan Gohman 45774ce0ad 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.

llvm-svn: 95975
2010-02-12 10:34:29 +00:00
Jakob Stoklund Olesen 93c92225af Reapply coalescer fix for better cross-class coalescing.
This time with fixed test cases.

llvm-svn: 95938
2010-02-11 23:55:29 +00:00
Dan Gohman 221708d826 Make SCEVAddRecExpr's getType return a pointer type when the add
has a pointer member. This helps reduce unnecessary bitcasting
and uglygeps.

llvm-svn: 93939
2010-01-19 22:53:50 +00:00
Dan Gohman 40503396da Eliminate more uses of llvm-as and llvm-dis.
llvm-svn: 81290
2009-09-08 23:54:48 +00:00
Bob Wilson 7f20002993 Stabilize the order of live intervals in the priority_queue used by the
linear scan reg alloc.  This fixes a problem I ran into where extracting
a function from a larger file caused the generated code to change (masking
the problem I was trying to debug) because the allocator behaved differently.

This changes the results for two X86 regression checks.  stack-color-with-reg
is improved, with one less instruction, but pr3495 is worse, with one more
copy.  As far as I can tell, these tests were just getting lucky or unlucky,
so I've changed the expected results.

llvm-svn: 81060
2009-09-05 01:19:16 +00:00
Dan Gohman f19aeec3f5 Extend ScalarEvolution's multiple-exit support to compute exact
trip counts in more cases.

Generalize ScalarEvolution's isLoopGuardedByCond code to recognize
And and Or conditions, splitting the code out into an
isNecessaryCond helper function so that it can evaluate Ands and Ors
recursively, and make SCEVExpander be much more aggressive about
hoisting instructions out of loops.

test/CodeGen/X86/pr3495.ll has an additional instruction now, but
it appears to be due to an arbitrary register allocation difference.

llvm-svn: 74048
2009-06-24 01:18:18 +00:00
Dale Johannesen 02cb2bf2e3 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.

llvm-svn: 71439
2009-05-11 17:15:42 +00:00
Dan Gohman 0a40ad93a9 Expand GEPs in ScalarEvolution expressions. SCEV expressions can now
have pointer types, though in contrast to C pointer types, SCEV
addition is never implicitly scaled. This not only eliminates the
need for special code like IndVars' EliminatePointerRecurrence
and LSR's own GEP expansion code, it also does a better job because
it lets the normal optimizations handle pointer expressions just
like integer expressions.

Also, since LLVM IR GEPs can't directly index into multi-dimensional
VLAs, moving the GEP analysis out of client code and into the SCEV
framework makes it easier for clients to handle multi-dimensional
VLAs the same way as other arrays.

Some existing regression tests show improved optimization.
test/CodeGen/ARM/2007-03-13-InstrSched.ll in particular improved to
the point where if-conversion started kicking in; I turned it off
for this test to preserve the intent of the test.

llvm-svn: 69258
2009-04-16 03:18:22 +00:00
Evan Cheng a1968b0fc7 Implement PR3495: local spiller optimization. The local spiller can now keep availability information over BB boundaries. It visits BB's in depth first order. After visiting a BB if it find a successor which has a single predecessor it visits the successor next without clearing the availability information. This allows the successor to omit reloads or change them into copies.
llvm-svn: 64298
2009-02-11 08:24:21 +00:00