Commit Graph

127 Commits

Author SHA1 Message Date
Chris Lattner
7e9b427c87 if an alloca is only ever accessed as a unit, and is accessed with load/store instructions,
then don't try to decimate it into its individual pieces.  This will just make a mess of the
IR and is pointless if none of the elements are individually accessed.  This was generating
really terrible code for std::bitset (PR8980) because it happens to be lowered by clang
as an {[8 x i8]} structure instead of {i64}.

The testcase now is optimized to:

define i64 @test2(i64 %X) {
  br label %L2

L2:                                               ; preds = %0
  ret i64 %X
}

before we generated:

define i64 @test2(i64 %X) {
  %sroa.store.elt = lshr i64 %X, 56
  %1 = trunc i64 %sroa.store.elt to i8
  %sroa.store.elt8 = lshr i64 %X, 48
  %2 = trunc i64 %sroa.store.elt8 to i8
  %sroa.store.elt9 = lshr i64 %X, 40
  %3 = trunc i64 %sroa.store.elt9 to i8
  %sroa.store.elt10 = lshr i64 %X, 32
  %4 = trunc i64 %sroa.store.elt10 to i8
  %sroa.store.elt11 = lshr i64 %X, 24
  %5 = trunc i64 %sroa.store.elt11 to i8
  %sroa.store.elt12 = lshr i64 %X, 16
  %6 = trunc i64 %sroa.store.elt12 to i8
  %sroa.store.elt13 = lshr i64 %X, 8
  %7 = trunc i64 %sroa.store.elt13 to i8
  %8 = trunc i64 %X to i8
  br label %L2

L2:                                               ; preds = %0
  %9 = zext i8 %1 to i64
  %10 = shl i64 %9, 56
  %11 = zext i8 %2 to i64
  %12 = shl i64 %11, 48
  %13 = or i64 %12, %10
  %14 = zext i8 %3 to i64
  %15 = shl i64 %14, 40
  %16 = or i64 %15, %13
  %17 = zext i8 %4 to i64
  %18 = shl i64 %17, 32
  %19 = or i64 %18, %16
  %20 = zext i8 %5 to i64
  %21 = shl i64 %20, 24
  %22 = or i64 %21, %19
  %23 = zext i8 %6 to i64
  %24 = shl i64 %23, 16
  %25 = or i64 %24, %22
  %26 = zext i8 %7 to i64
  %27 = shl i64 %26, 8
  %28 = or i64 %27, %25
  %29 = zext i8 %8 to i64
  %30 = or i64 %29, %28
  ret i64 %30
}

In this case, instcombine was able to eliminate the nonsense, but in PR8980 enough
PHIs are in play that instcombine backs off.  It's better to not generate this stuff
in the first place.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123571 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-16 06:18:28 +00:00
Bob Wilson
704d1347c5 Extend SROA to handle arrays accessed as homogeneous structs and vice versa.
This is a minor extension of SROA to handle a special case that is
important for some ARM NEON operations.  Some of the NEON intrinsics
return multiple values, which are handled as struct types containing
multiple elements of the same vector type.  The corresponding return
types declared in the arm_neon.h header have equivalent arrays.  We
need SROA to recognize that it can split up those arrays and structs
into separate vectors, even though they are not always accessed with
the same type.  SROA already handles loads and stores of an entire
alloca by using insertvalue/extractvalue to access the individual
pieces, and that code works the same regardless of whether the type
is a struct or an array.  So, all that needs to be done is to check
for compatible arrays and homogeneous structs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123381 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-13 17:45:11 +00:00
Bob Wilson
694a10e7d8 Make SROA more aggressive with allocas containing padding.
SROA only split up structs and arrays one level at a time, so padding can
only cause trouble if it is located in between the struct or array elements.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123380 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-13 17:45:08 +00:00
Nick Lewycky
081f80078d Treat a call of function pointer like a load of the pointer when considering
whether the pointer can be replaced with the global variable it is a copy of.
Fixes PR8680.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120126 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-24 22:04:20 +00:00
Chris Lattner
6248065194 allow eliminating an alloca that is just copied from an constant global
if it is passed as a byval argument.  The byval argument will just be a
read, so it is safe to read from the original global instead.  This allows
us to promote away the %agg.tmp alloca in PR8582


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119686 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-18 06:41:51 +00:00
Chris Lattner
a9be1df6d7 enhance the "alloca is just a memcpy from constant global"
to ignore calls that obviously can't modify the alloca
because they are readonly/readnone.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119683 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-18 06:26:49 +00:00
Chris Lattner
2e61849f45 fix a small oversight in the "eliminate memcpy from constant global"
optimization.  If the alloca that is "memcpy'd from constant" also has
a memcpy from *it*, ignore it: it is a load.  We now optimize the testcase to:

define void @test2() {
  %B = alloca %T
  %a = bitcast %T* @G to i8*
  %b = bitcast %T* %B to i8*
  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %b, i8* %a, i64 124, i32 4, i1 false)
  call void @bar(i8* %b)
  ret void
}

previously we would generate:

define void @test() {
  %B = alloca %T
  %b = bitcast %T* %B to i8*
  %G.0 = getelementptr inbounds %T* @G, i32 0, i32 0
  %tmp3 = load i8* %G.0, align 4
  %G.1 = getelementptr inbounds %T* @G, i32 0, i32 1
  %G.15 = bitcast [123 x i8]* %G.1 to i8*
  %1 = bitcast [123 x i8]* %G.1 to i984*
  %srcval = load i984* %1, align 1
  %B.0 = getelementptr inbounds %T* %B, i32 0, i32 0
  store i8 %tmp3, i8* %B.0, align 4
  %B.1 = getelementptr inbounds %T* %B, i32 0, i32 1
  %B.12 = bitcast [123 x i8]* %B.1 to i8*
  %2 = bitcast [123 x i8]* %B.1 to i984*
  store i984 %srcval, i984* %2, align 1
  call void @bar(i8* %b)
  ret void
}



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119682 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-18 06:20:47 +00:00
Chris Lattner
d222e36b49 filecheckize
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119681 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-18 06:16:43 +00:00
Chris Lattner
72eaa0e5eb deepen my MMX/SRoA hack to avoid hurting non-x86 codegen.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112763 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-01 23:09:27 +00:00
Chris Lattner
91abace4ef add a gross hack to work around a problem that Argiris reported
on llvmdev: SRoA is introducing MMX datatypes like <1 x i64>,
which then cause random problems because the X86 backend is
producing mmx stuff without inserting proper emms calls.

In the short term, force off MMX datatypes.  In the long term,
the X86 backend should not select generic vector types to MMX
registers.  This is being worked on, but won't be done in time
for 2.8.  rdar://8380055


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112696 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-01 05:14:33 +00:00
Chris Lattner
54d24025d6 filecheckize
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112695 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-01 05:10:14 +00:00
Chris Lattner
0238f8c430 Fix the second half of PR7437: scalarrepl wasn't preserving
address spaces when SRoA'ing memcpy's.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107846 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-08 00:27:05 +00:00
Rafael Espindola
1e81966626 Remove arm_apcscc from the test files. It is the default and doing this
matches what llvm-gcc and clang now produce.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106221 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-17 15:18:27 +00:00
Rafael Espindola
2ebb4f81f7 Remove the arm_aapcscc marker from the tests. It is the default
for the linux targets.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106029 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-15 19:04:29 +00:00
Chris Lattner
5f0378251c move comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101433 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-16 01:05:52 +00:00
Chris Lattner
d55c1c1659 fix PR6832: we were using the alignment of a pointer when we
wanted the alignment of the pointee.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101432 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-16 01:05:38 +00:00
Devang Patel
09a695e396 Remove tests that checks @llvm.dbg.stoppoint handling.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97493 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-01 20:33:48 +00:00
Bob Wilson
a756b1d914 Fix a crash in scalarrepl for memcpy/memmove where the source and destination
are the same.  I had already fixed a similar problem where the source and
destination were different bitcasts derived from the same alloca, but the
previous fix still did not handle the case where both operands are exactly
the same value.  Radar 7552893.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93848 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-19 04:32:48 +00:00
Dan Gohman
aceba31b7a Delete useless trailing semicolons.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92740 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 17:55:26 +00:00
Bob Wilson
f27a4cd783 Generalize SROA to allow the first index of a GEP to be non-zero. Add a
missing check that an array reference doesn't go past the end of the array,
and remove some redundant checks for in-bound array and vector references
that are no longer needed.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91897 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-22 06:57:14 +00:00
Bob Wilson
b742defa0a Reapply 91459 with a simple fix for the problem that broke the x86_64-darwin
bootstrap.  This also replaces the WeakVH references that Chris objected to
with normal Value references.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91711 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-18 20:14:40 +00:00
Bob Wilson
39c88a641b Re-revert 91459. It's breaking the x86_64 darwin bootstrap.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91607 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-17 18:34:24 +00:00
Daniel Dunbar
2674089cef Reapply r91459, it was only unmasking the bug, and since TOT is still broken having it reverted does no good.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91559 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-16 20:09:53 +00:00
Daniel Dunbar
fca55c8ac7 Revert "Reapply 91184 with fixes and an addition to the testcase to cover the
problem", this broke llvm-gcc bootstrap for release builds on
x86_64-apple-darwin10.

This reverts commit db22309800b224a9f5f51baf76071d7a93ce59c9.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91534 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-16 10:56:17 +00:00
Bob Wilson
970eaf2520 Reapply 91184 with fixes and an addition to the testcase to cover the problem
found last time.  Instead of trying to modify the IR while iterating over it,
I've change it to keep a list of WeakVH references to dead instructions, and
then delete those instructions later.  I also added some special case code to
detect and handle the situation when both operands of a memcpy intrinsic are
referencing the same alloca.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91459 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-15 22:00:51 +00:00
Shantonu Sen
bc1c99c4fb Remove empty file completely
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91277 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-14 14:15:15 +00:00
Chris Lattner
a59adc4015 revert r91184, because it causes a crash on a .bc file I just
sent to Bob.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91268 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-14 05:11:02 +00:00
Bob Wilson
73a1b67cb9 Revise scalar replacement to be more flexible about handle bitcasts and GEPs.
While scanning through the uses of an alloca, keep track of the current offset
relative to the start of the alloca, and check memory references to see if
the offset & size correspond to a component within the alloca.  This has the
nice benefit of unifying much of the code from isSafeUseOfAllocation,
isSafeElementUse, and isSafeUseOfBitCastedAllocation.  The code to rewrite
the uses of a promoted alloca, after it is determined to be safe, is
reorganized in the same way.

Also, when rewriting GEP instructions, mark them as "in-bounds" since all the
indices are known to be safe.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91184 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-11 23:47:40 +00:00
Chris Lattner
8976e5950f fix PR5436 by making the 'simple' case of SRoA not promote out of range
array indexes.  The "complex" case of SRoA still handles them, and correctly.

This fixes a weirdness where we'd correctly avoid transforming A[0][42] if
the 42 was too large, but we'd only do it if it was one gep, not two separate
ones.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90007 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-27 16:37:41 +00:00
Chris Lattner
fc159fd741 filecheckize
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90006 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-27 16:31:59 +00:00
Kenneth Uildriks
b908f8ad6a Make opt default to not adding a target data string and update tests that depend on target data to supply it within the test
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85900 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-03 15:29:06 +00:00
Dan Gohman
f2f6ce65b7 Change tests from "opt %s" to "opt < %s" so that opt doesn't see the
input filename so that opt doesn't print the input filename in the
output so that grep lines in the tests don't unintentionally match
strings in the input filename.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81537 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-11 18:01:28 +00:00
Dan Gohman
3e054fe9ef Use opt -S instead of piping bitcode output through llvm-dis.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81257 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-08 22:34:10 +00:00
Dan Gohman
b1e1e82c54 Change these tests to feed the assembly files to opt directly, instead
of using llvm-as, now that opt supports this.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81226 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-08 16:50:01 +00:00
Nick Lewycky
d3aa25e2a8 Don't crash trying to promote VLAs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79226 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-17 05:37:31 +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
Eli Friedman
41b33f437f PR4286: Make RewriteLoadUserOfWholeAlloca and
RewriteStoreUserOfWholeAlloca deal with tail padding because 
isSafeUseOfBitCastedAllocation expects them to.  Otherwise, we crash 
trying to erase the bitcast.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72688 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-01 09:14:32 +00:00
Chris Lattner
ef554846f0 fix RewriteStoreUserOfWholeAlloca to use the correct type size
method, fixing a crash on PR4146.  While the store will 
ultimately overwrite the "padded size" number of bits in memory,
the stored value may be a subset of this size.  This function
only wants to handle the case where all bits are stored.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71224 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-08 15:54:41 +00:00
Chris Lattner
33e24adc3b fix a crash on a pointless but valid zero-length memset, rdar://6808691
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69680 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-21 16:52:12 +00:00
Zhou Sheng
df95a2f6a9 Fix a bug.
If I->use_empty(), this method should return false.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@67180 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-18 07:56:13 +00:00
Chris Lattner
29e641761e teach SROA to handle promoting vector allocas with a memset into them into
a vector type instead of into an integer type.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66368 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-08 04:17:04 +00:00
Chris Lattner
c570487d45 Enhance SROA to "promote to scalar" allocas which are
memcpy/memmove'd into or out of.  This fixes a serious
perf issue that Nate ran into.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66366 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-08 04:04:21 +00:00
Devang Patel
00e389c8c8 While converting an aggregate to scalare, ignore and remove aggregate's debug info.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66262 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-06 07:03:54 +00:00
Chris Lattner
1541e0f7da Fix PR3720 by properly propagating alignment information from memcpy/memmove
onto element accesses.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66053 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-04 19:20:50 +00:00
Chris Lattner
585cfb6821 adjust for asmprinter change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65741 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-01 00:26:51 +00:00
Devang Patel
4afc90dacf Enable scalar replacement of AllocaInst whose one of the user is dbg info.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64207 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-10 07:00:59 +00:00
Chris Lattner
e991ced7cb fix PR3489, use bits instead of bytes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63916 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-06 04:34:07 +00:00
Chris Lattner
1aa7056b13 teach "convert from scalar" to handle loads of fca's.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63659 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-03 21:08:45 +00:00
Chris Lattner
9b872db775 make scalar conversion handle stores of first class
aggregate values.  loads are not yet handled (coming
soon to an sroa near you).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63649 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-03 19:30:11 +00:00
Chris Lattner
1a3257bbf5 Make SROA produce a vector only when the alloca is actually
accessed at least once as a vector.  This prevents it from
compiling the example in not-a-vector into:

define double @test(double %A, double %B) {
	%tmp4 = insertelement <7 x double> undef, double %A, i32 0
	%tmp = insertelement <7 x double> %tmp4, double %B, i32 4
	%tmp2 = extractelement <7 x double> %tmp, i32 4
	ret double %tmp2
}

instead, producing the integer code.  Producing vectors when they
aren't otherwise in the program is dangerous because a lot of other
code treats them carefully and doesn't want to break them down.
OTOH, many things want to break down tasty i448's.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63638 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-03 18:15:05 +00:00