Commit Graph

1209 Commits

Author SHA1 Message Date
Chris Lattner 61797e3291 Fix 4366: store to null in non-default addr space should not be
turned into unreachable.

llvm-svn: 73195
2009-06-11 17:54:56 +00:00
Eli Friedman 73a83066d5 PR4340: Run SimplifyDemandedVectorElts on insertelement instructions;
sometimes it can find simplifications that won't be found otherwise.

llvm-svn: 73006
2009-06-06 20:08:03 +00:00
Dan Gohman a5b9645c4b 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

llvm-svn: 72897
2009-06-04 22:49:04 +00:00
Dan Gohman 7b6b5dd954 Don't do the X * 0.0 -> 0.0 transformation in instcombine, because
instcombine doesn't know when it's safe. To partially compensate
for this, introduce new code to do this transformation in
dagcombine, which can use UnsafeFPMath.

llvm-svn: 72872
2009-06-04 17:12:12 +00:00
Evan Cheng a838a40bc4 Fix bug in FoldFCmp_IntToFP_Cst. If inttofp is a uintofp, use unsigned instead of signed integer constant.
llvm-svn: 72300
2009-05-22 23:10:53 +00:00
Dan Gohman bf0002e7c1 Teach ValueTracking a new way to analyze PHI nodes, and and teach
Instcombine to be more aggressive about using SimplifyDemandedBits
on shift nodes. This allows a shift to be simplified to zero in the
included test case.

llvm-svn: 72204
2009-05-21 02:28:33 +00:00
Chris Lattner 149546a6a0 calls in nothrow functions can be marked nothrow even if the callee
is not known to be nothrow.  This allows readnone/readonly functions
to be deleted even if we don't know whether the callee can throw.

llvm-svn: 71676
2009-05-13 17:39:14 +00:00
Duncan Sands af9eaa830a Rename PaddedSize to AllocSize, in the hope that this
will make it more obvious what it represents, and stop
it being confused with the StoreSize.

llvm-svn: 71349
2009-05-09 07:06:46 +00:00
Nick Lewycky 702fbf94a0 This transform requires valid TargetData info. Wrap it in 'if (TD)' in
preparation for the day we use null TargetData when no target is specified.

llvm-svn: 71210
2009-05-08 06:47:37 +00:00
Dan Gohman 140a6f24f0 Perform constant folding on operands of instructions with non-void
types, such as loads and calls.

llvm-svn: 71175
2009-05-07 19:43:39 +00:00
Duncan Sands 1efabaaa2a Allow readonly functions to unwind exceptions. Teach
the optimizers about this.  For example, a readonly
function with no uses cannot be removed unless it is
also marked nounwind.

llvm-svn: 71071
2009-05-06 06:49:50 +00:00
Dan Gohman 1b5055ab7f Return null instead of false, as appropriate.
llvm-svn: 70054
2009-04-25 17:28:45 +00:00
Dan Gohman 5638e0d642 Add several more icmp simplifications. Transform signed comparisons
into unsigned ones when the operands are known to have the same
sign bit value.

llvm-svn: 70053
2009-04-25 17:12:48 +00:00
Sanjiv Gupta 46c97e626f Allow i16 type indices to gep.
llvm-svn: 69946
2009-04-24 02:37:54 +00:00
Sanjiv Gupta 428d490332 Before trying to introduce/eliminate cast/ext/trunc to make indices type as
pointer type, make sure that the pointer size is a valid sequential index type.

llvm-svn: 69574
2009-04-20 06:05:54 +00:00
Chris Lattner eb510d6b3d Instcombine should not promote whole computation trees to "strange"
integer types, unless they are already strange.  This prevents it from
turning the code produced by SROA into crazy libcalls and stuff that 
the code generator can't handle.  In the attached example, the result
was an i96 multiply that caused the x86 backend to assert.

Note that if TargetData had an idea of what the legal types are for
a target that this could be used to stop instcombine from introducing
i64 muls, as Scott wanted.

llvm-svn: 68598
2009-04-08 05:41:03 +00:00
Chris Lattner 321741af5f fix rdar://6762290, a crash compiling cxx filt with clang.
llvm-svn: 68500
2009-04-07 05:03:34 +00:00
Evan Cheng 826b6f0f7c Throttle back "fold select into operand" transformation. InstCombine should not generate selects of two constants unless they are selects of 0 and 1.
e.g.
define i32 @t1(i32 %c, i32 %x) nounwind {
       %t1 = icmp eq i32 %c, 0
       %t2 = lshr i32 %x, 18
       %t3 = select i1 %t1, i32 %t2, i32 %x
       ret i32 %t3
}

was turned into

define i32 @t2(i32 %c, i32 %x) nounwind {
       %t1 = icmp eq i32 %c, 0
       %t2 = select i1 %t1, i32 18, i32 0
       %t3 = lshr i32 %x, %t2
       ret i32 %t3
}

For most targets, that means materializing two constants and then a select. e.g. On x86-64

movl    %esi, %eax
shrl    $18, %eax
testl   %edi, %edi
cmovne  %esi, %eax
ret

=>

xorl    %eax, %eax
testl   %edi, %edi
movl    $18, %ecx
cmovne  %eax, %ecx
movl    %esi, %eax
shrl    %cl, %eax
ret

Also, the optimizer and codegen can reason about shl / and / add, etc. by a constant. This optimization will hinder optimizations using ComputeMaskedBits.

llvm-svn: 68142
2009-03-31 20:42:45 +00:00
Chris Lattner c3b2111d97 Fix PR3874 by restoring a condition I removed, but making it more
precise than it used to be.

llvm-svn: 67662
2009-03-25 00:28:58 +00:00
Chris Lattner 9e94538005 oops, I intended to remove this, not comment it out. Thanks Duncan!
llvm-svn: 67657
2009-03-24 23:48:25 +00:00
Chris Lattner 306813cbbb canonicalize inttoptr and ptrtoint instructions which cast pointers
to/from integer types that are not intptr_t to convert to intptr_t
then do an integer conversion to the dest type.  This exposes the
cast to the optimizer.

llvm-svn: 67638
2009-03-24 18:35:40 +00:00
Chris Lattner d9eb41177a two changes:
1. Make instcombine always canonicalize trunc x to i1 into an icmp(x&1).  This 
   exposes the AND to other instcombine xforms and is more of what the code
   generator expects.
2. Rewrite the remaining trunc pattern match to use 'match', which 
   simplifies it a lot.
   

llvm-svn: 67635
2009-03-24 18:15:30 +00:00
Duncan Sands 1f15ca7c7a Factorize out a concept - no functionality change.
llvm-svn: 67454
2009-03-21 21:27:31 +00:00
Chris Lattner 0a981d1d36 Fix instcombine to not introduce undefined shifts when merging two
shifts together.  This fixes PR3851.

llvm-svn: 67411
2009-03-20 22:41:15 +00:00
Duncan Sands a09e0afe74 Don't load values out of global constants with weak
linkage: the value may be replaced with something
different at link time.  (Frontends that want to
allow values to be loaded out of weak constants can
give their constants weak_odr linkage).

llvm-svn: 67407
2009-03-20 21:53:29 +00:00
Chris Lattner 595923ff75 Fix PR3826 - InstComb assert with vector shift, by not calling ComputeNumSignBits on a vector.
llvm-svn: 67211
2009-03-18 16:32:19 +00:00
Chris Lattner e549493a55 Remove a condition which is always true.
llvm-svn: 67089
2009-03-17 17:55:15 +00:00
Dale Johannesen c65830519e One more place where debug info affects codegen.
llvm-svn: 66930
2009-03-13 19:23:20 +00:00
Bill Wendling fa54bc2052 Oops...I committed too much.
llvm-svn: 66867
2009-03-13 04:39:26 +00:00
Bill Wendling b02eadf660 Temporarily XFAIL this test.
llvm-svn: 66866
2009-03-13 04:37:11 +00:00
Dale Johannesen 08ccba73a7 Skip interleaved debug info when fast-forwarding through
allocations.  Apparently the assumption is there is an
instruction (terminator?) following the allocation so I
am allowing the same assumption.

llvm-svn: 66716
2009-03-11 22:19:43 +00:00
Dale Johannesen 703703aacb Removing a dead debug intrinsic shouldn't trigger
another instcombine pass if we weren't going to make
one without debug info.

llvm-svn: 66576
2009-03-10 21:19:49 +00:00
Chris Lattner dc35e5b43a change the MemIntrinsic get/setAlignment method to take an unsigned
instead of a Constant*, which is what the clients of it really want.

llvm-svn: 66364
2009-03-08 03:59:00 +00:00
Chris Lattner 334268a211 Introduce a new MemTransferInst pseudo class, which is a common
parent between MemCpyInst and MemMoveInst, simplify some code to
use it.

llvm-svn: 66361
2009-03-08 03:37:16 +00:00
Dale Johannesen 78ab338024 Fix another case where debug info was affecting
codegen.  I convinced myself it was OK to skip all
pointer bitcasts here too.

llvm-svn: 66122
2009-03-05 02:06:48 +00:00
Dale Johannesen ad6b47377f Fix another case where a dbg.declare meant something
had 2 uses instead of 1.

llvm-svn: 66112
2009-03-05 00:39:02 +00:00
Dale Johannesen c8b5a6ef7d Always skip ptr-to-ptr bitcasts when counting,
per Chris' suggestion.  Slightly faster.

llvm-svn: 65999
2009-03-04 01:53:05 +00:00
Dale Johannesen 0365d3b8b5 Make my earlier patch to skip debug intrinsics
when counting work; it was only off by 1.

llvm-svn: 65993
2009-03-04 01:20:34 +00:00
Dale Johannesen 09c3e8ec00 Instruction counters must skip the bitcasts that
feed into llvm.dbg.declare nodes, as well as
the debug directives themselves.

llvm-svn: 65976
2009-03-03 22:36:47 +00:00
Dale Johannesen 77456b7ab4 When removing a store to an alloca that has only one
use, check also for the case where it has two uses,
the other being a llvm.dbg.declare.  This is needed so
debug info doesn't affect codegen.

llvm-svn: 65970
2009-03-03 21:26:39 +00:00
Dan Gohman 92b551bc2b Fix a bunch of Doxygen syntax issues. Escape special characters,
and put @file directives on their own comment line.

llvm-svn: 65920
2009-03-03 02:55:14 +00:00
Dale Johannesen 0192552340 Don't count DebugInfo instructions in another limit
(lest they affect codegen).

llvm-svn: 65915
2009-03-03 01:43:03 +00:00
Dale Johannesen e1bb2f86f9 When sinking an insn in InstCombine bring its debug
info with it.
Don't count debug info insns against the scan maximum
in FindAvailableLoadedValue (lest they affect codegen).

llvm-svn: 65910
2009-03-03 01:09:07 +00:00
Duncan Sands 5795a6091d Fix PR3694: add an instcombine micro-optimization that helps
clean up when using variable length arrays in llvm-gcc.

llvm-svn: 65832
2009-03-02 09:18:21 +00:00
Nick Lewycky 34709f84d8 Silence compiler warning about use of uninitialized variables (in reality these
are always set by reference on the path that uses them.) No functional change.

llvm-svn: 65621
2009-02-27 06:37:39 +00:00
Chris Lattner af618171f4 Fix PR3667
llvm-svn: 65464
2009-02-25 18:20:01 +00:00
Dan Gohman 4f356bb9b0 Fix a ValueTracking rule: RHS means operand 1, not 0. Add a simple
ashr instcombine to help expose this code. And apply the fix to
SelectionDAG's copy of this code too.

llvm-svn: 65364
2009-02-24 02:00:40 +00:00
Zhou Sheng 3a86bcf134 Should reset DBI_Prev if DBI_Next == 0.
llvm-svn: 65314
2009-02-23 10:14:11 +00:00
Chris Lattner d5420f0957 fix some typos that Duncan noticed
llvm-svn: 65306
2009-02-23 05:56:17 +00:00
Dan Gohman 648c5e9c99 Revert the part of 64623 that attempted to align the source in a
memcpy to match the alignment of the destination. It isn't necessary
for making loads and stores handled like the SSE loadu/storeu
intrinsics, and it was causing a performance regression in
MultiSource/Applications/JM/lencod.

The problem appears to have been a memcpy that copies from some
highly aligned array into an alloca; the alloca was then being
assigned a large alignment, which required codegen to perform
dynamic stack-pointer re-alignment, which forced the enclosing
function to have a frame pointer, which led to increased spilling.

llvm-svn: 65289
2009-02-22 18:06:32 +00:00