llvm-svn: 50106

  br (and X, phi(Y, Z, false)), label L1, label L2

This triggers once on 252.eon and 6 times on 176.gcc.  Blocks 
in question often look like this:

bb262:		; preds = %bb261, %bb248
	%iftmp.251.0 = phi i1 [ true, %bb261 ], [ false, %bb248 ]		; <i1> [#uses=4]
	%tmp270 = icmp eq %struct.rtx_def* %tmp.0.i, null		; <i1> [#uses=1]
	%bothcond = or i1 %iftmp.251.0, %tmp270		; <i1> [#uses=1]
	br i1 %bothcond, label %bb288, label %bb273

In this case, it is clear that it doesn't matter if tmp.0.i is null when coming from bb261.  When coming from bb248, it is all that matters.


Another random example:

check_asm_operands.exit:		; preds = %check_asm_operands.exit.thr_comm, %bb30.i, %bb12.i, %bb6.i413
	%tmp.0.i420 = phi i1 [ true, %bb6.i413 ], [ true, %bb12.i ], [ true, %bb30.i ], [ false, %check_asm_operands.exit.thr_comm ; <i1> [#uses=1]
	call void @llvm.stackrestore( i8* %savedstack ) nounwind 
	%tmp4389 = icmp eq i32 %added_sets_1.0, 0		; <i1> [#uses=1]
	%tmp4394 = icmp eq i32 %added_sets_2.0, 0		; <i1> [#uses=1]
	%bothcond80 = and i1 %tmp4389, %tmp4394		; <i1> [#uses=1]
	%bothcond81 = and i1 %bothcond80, %tmp.0.i420		; <i1> [#uses=1]
	br i1 %bothcond81, label %bb4398, label %bb4397

Here is the case from 252.eon:

bb290.i.i:		; preds = %bb23.i57.i.i, %bb8.i39.i.i, %bb100.i.i, %bb100.i.i, %bb85.i.i110
	%myEOF.1.i.i = phi i1 [ true, %bb100.i.i ], [ true, %bb100.i.i ], [ true, %bb85.i.i110 ], [ true, %bb8.i39.i.i ], [ false, %bb23.i57.i.i ]		; <i1> [#uses=2]
	%i.4.i.i = phi i32 [ %i.1.i.i, %bb85.i.i110 ], [ %i.0.i.i, %bb100.i.i ], [ %i.0.i.i, %bb100.i.i ], [ %i.3.i.i, %bb8.i39.i.i ], [ %i.3.i.i, %bb23.i57.i.i ]		; <i32> [#uses=3]
	%tmp292.i.i = load i8* %tmp16.i.i100, align 1		; <i8> [#uses=1]
	%tmp293.not.i.i = icmp ne i8 %tmp292.i.i, 0		; <i1> [#uses=1]
	%bothcond.i.i = and i1 %tmp293.not.i.i, %myEOF.1.i.i		; <i1> [#uses=1]
	br i1 %bothcond.i.i, label %bb202.i.i, label %bb301.i.i
  Factoring out 3 common predecessors.

On the path from any blocks other than bb23.i57.i.i, the load and compare 
are dead.

llvm-svn: 50096

llvm-svn: 50094

llvm-svn: 50080

getelementptr-seteq.ll into:

define i1 @test(i64 %X, %S* %P) {
	%C = icmp eq i64 %X, -1		; <i1> [#uses=1]
	ret i1 %C
}

instead of:

define i1 @test(i64 %X, %S* %P) {
	%A.idx.mask = and i64 %X, 4611686018427387903		; <i64> [#uses=1]
	%C = icmp eq i64 %A.idx.mask, 4611686018427387903		; <i1> [#uses=1]
	ret i1 %C
}

And fixes the second half of PR2235.  This speeds up the insertion sort
case by 45%, from 1.12s to 0.77s.  In practice, this will significantly
speed up for loops structured like:

for (double *P = Base + N; P != Base; --P)
  ...

Which happens frequently for C++ iterators.

llvm-svn: 50079

llvm-svn: 50047

llvm-svn: 50035

and simplify code that was fallout from the separation of memcpyopt and gvn.

llvm-svn: 50034

fixes a crash in opt on 433.milc.

llvm-svn: 50023

llvm-svn: 50022

as a global helper function.  At the same type, switch it from taking
a vector of predecessors to an arbitrary sequential input.  This allows
us to switch LoopSimplify to use a SmallVector for various temporary
vectors that it passed into SplitBlockPredecessors.

llvm-svn: 50020

nodes, removing a hack.

llvm-svn: 50019

instead of doing it after every call.

llvm-svn: 50018

llvm-svn: 50016

llvm-svn: 50015

llvm-svn: 50014

llvm-svn: 50006

a call to Instruction::isUsedOutsideOfBlock.

llvm-svn: 50005

llvm-svn: 50003

Add a cost function.

llvm-svn: 50002

such as those in PR2235.  Right now the pass is not very
effective. :)

llvm-svn: 50000

llvm-svn: 49989

llvm-svn: 49977

of elements.  Patch by Matthijs Kooijman!

llvm-svn: 49962

llvm-svn: 49842

llvm-svn: 49838

wee problem in Xcode 2.[45]/gcc 4.0.1.

llvm-svn: 49831

VisualStudio project files updated.  #include <algorithm> added to make VisualStudio happy.  Also had to undefine setjmp because of #include <csetjmp> turning setjmp into _setjmp in VisualStudio.

llvm-svn: 49743

llvm-svn: 49681

llvm-svn: 49671

llvm-svn: 49657

which is significantly more efficient.

llvm-svn: 49614

of calls and less aggressive with non-readnone calls.

llvm-svn: 49516

in addition to integer expressions. Rewrite GetOrEnforceKnownAlignment
as a ComputeMaskedBits problem, moving all of its special alignment
knowledge to ComputeMaskedBits as low-zero-bits knowledge.

Also, teach ComputeMaskedBits a few basic things about Mul and PHI
instructions.

This improves ComputeMaskedBits-based simplifications in a few cases,
but more noticeably it significantly improves instcombine's alignment
detection for loads, stores, and memory intrinsics.

llvm-svn: 49492

This is not safe for all inputs.

llvm-svn: 49458

figuring out the suffix to use.  implement pow(2,x) -> exp2(x).

llvm-svn: 49437

long double and simplify the code.

llvm-svn: 49435

llvm-svn: 49430

GVN and into its own pass.

llvm-svn: 49419

llvm-svn: 49418