[Intrinsics] Add `nocallback` to the memset/cpy/move intrinsics

These were forgotten when D118680 was applied. Similar to D125937.

Differential Revision: https://reviews.llvm.org/D129516

[FunctionAttrs] Infer argmemonly .

This patch adds initial argmemonly inference, by checking the underlying
objects of locations returned by MemoryLocation.

I think this should cover most cases, ex

[FunctionAttrs] Infer argmemonly .

This patch adds initial argmemonly inference, by checking the underlying
objects of locations returned by MemoryLocation.

I think this should cover most cases, except function calls to other
argmemonly functions.

I'm not sure if there's a reason why we don't infer those yet.

Additional argmemonly can improve codegen in some cases. It also makes
it easier to come up with a C reproducer for 7662d1687b09 (already fixed,
but I'm trying to see if C/C++ fuzzing could help to uncover similar
issues.)

Compile-time impact:
NewPM-O3: +0.01%
NewPM-ReleaseThinLTO: +0.03%
NewPM-ReleaseLTO+g: +0.05%

https://llvm-compile-time-tracker.com/compare.php?from=067c035012fc061ad6378458774ac2df117283c6&to=fe209d4aab5b593bd62d18c0876732ddcca1614d&stat=instructions

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D121415

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[funcattrs] Infer writeonly argument attribute [part 2]

This builds on the code from D114963, and extends it to handle calls both direct and indirect. With the revised code structure (from series of

[funcattrs] Infer writeonly argument attribute [part 2]

This builds on the code from D114963, and extends it to handle calls both direct and indirect. With the revised code structure (from series of previously landed NFCs), this is pretty straight forward.

One thing to note is that we can not infer writeonly for arguments which might be captured. If the pointer can be read back by the caller, and then read through, we have no way to track that. This is the same restriction we have for readonly, except that we get no mileage out of the "callee can be readonly" exception since a writeonly param on a readonly function is either a) readnone or b) UB. This means we can't actually infer much unless nocapture has already been inferred.

Differential Revision: https://reviews.llvm.org/D115003

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[funcattrs] Infer writeonly argument attribute

This change extends the current logic for inferring readonly and readnone argument attributes to also infer writeonly.

This change is deliberately min

[funcattrs] Infer writeonly argument attribute

This change extends the current logic for inferring readonly and readnone argument attributes to also infer writeonly.

This change is deliberately minimal; there's a couple of areas for follow up.
* I left out all call handling and thus any benefit from the SCC walk. When examining the test changes, I realized the existing code is imprecise, and am going to fix that in it's own revision before adding in the writeonly handling. (Mostly because updating the tests is hard when I, the human, can't figure out whether the result is correct.)
* I left out handling for storing a value (as opposed to storing to a pointer). This should benefit readonly/readnone as well, and applies to a bunch of other instructions. Seemed worth having as a separate review.

Differential Revision: https://reviews.llvm.org/D114963

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Reapply [IR] Don't mark mustprogress as type attribute

Reapply with fixes for clang tests.

-----

This is a simple enum attribute. Test changes are because enum
attributes are sorted before type at

Reapply [IR] Don't mark mustprogress as type attribute

Reapply with fixes for clang tests.

-----

This is a simple enum attribute. Test changes are because enum
attributes are sorted before type attributes, so mustprogress is
now in a different position.

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Revert "[IR] Don't mark mustprogress as type attribute"

This reverts commit 84ed3a794b4ffe7bd673f1e5a17d507aa3113d12.

A number of clang tests are also affected by this change. Revert
until I can up

Revert "[IR] Don't mark mustprogress as type attribute"

This reverts commit 84ed3a794b4ffe7bd673f1e5a17d507aa3113d12.

A number of clang tests are also affected by this change. Revert
until I can update them.

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[IR] Don't mark mustprogress as type attribute

This is a simple enum attribute.

Test changes are because enum attributes are sorted before type
attributes.

[IR] Memory intrinsics are not unconditionally `nosync`

Remove the `nosync` attribute from the memory intrinsic definitions
(i.e. memset, memcpy, memmove).

Like native memory accesses, memory intri

[IR] Memory intrinsics are not unconditionally `nosync`

Remove the `nosync` attribute from the memory intrinsic definitions
(i.e. memset, memcpy, memmove).

Like native memory accesses, memory intrinsics can be volatile. This is
indicated by an immarg in the intrinsic call. All else equal, a volatile
memory intrinsic is `sync`, so we cannot annotate the intrinsic functions
themselves as `nosync`. The attributor and function-attr passes know to
take the volatile bit into account.

Since `nosync` is a default attribute, this means we have to stop using
the DefaultAttrIntrinsic tablegen class for memory intrinsics, and
specify all default attributes other than `nosync` explicitly.

Most of the test changes are trivial churn, but one test case
(in nosync.ll) was in fact incorrect before this change.

Differential Revision: https://reviews.llvm.org/D102295

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[test] Fix some func-attrs tests under the legacy PM

The new PM doesn't visit declarations in CGSCC passes. These tests
aren't testing that detail, so just run them against the new PM.

[funcattrs] Add the maximal set of implied attributes to definitions

Have funcattrs expand all implied attributes into the IR. This expands the infrastructure from D100400, but for definitions not d

[funcattrs] Add the maximal set of implied attributes to definitions

Have funcattrs expand all implied attributes into the IR. This expands the infrastructure from D100400, but for definitions not declarations this time.

Somewhat subtly, this mostly isn't semantic. Because the accessors did the inference, any client which used the accessor was already getting the stronger result. Clients that directly checked presence of attributes (there are some), will see a stronger result now.

The old behavior can end up quite confusing for two reasons:
* Without this change, we have situations where function-attrs appears to fail when inferring an attribute (as seen by a human reading IR), but that consuming code will see that it should have been implied. As a human trying to sanity check test results and study IR for optimization possibilities, this is exceeding error prone and confusing. (I'll note that I wasted several hours recently because of this.)
* We can have transforms which trigger without the IR appearing (on inspection) to meet the preconditions. This change doesn't prevent this from happening (as the accessors still involve multiple checks), but it should make it less frequent.

I'd argue in favor of deleting the extra checks out of the accessors after this lands, but I want that in it's own review as a) it's purely stylistic, and b) I already know there's some disagreement.

Once this lands, I'm also going to do a cleanup change which will delete some now redundant duplicate predicates in the inference code, but again, that deserves to be a change of it's own.

Differential Revision: https://reviews.llvm.org/D100226

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[funcattrs] Infer nosync from instruction walk

Pretty straightforward use of existing infrastructure and port of the attributor inference rules for nosync.

A couple points of interest:
* I delibera

[funcattrs] Infer nosync from instruction walk

Pretty straightforward use of existing infrastructure and port of the attributor inference rules for nosync.

A couple points of interest:
* I deliberately switched from "monotonic or better" to "unordered or better". This is simply me being conservative and is better in line with the rest of the optimizer. We treat monotonic conservatively pretty much everywhere.
* The operand bundle test change is suspicious. It looks like we might have missed something here, but if so, it's an issue with the existing nofree inference as well. I'm going to take a closer look at that separately.
* I needed to keep the previous inference from readnone. This surprised me, but made sense once I realized readonly inference goes to lengths to reason about local vs non-local memory and that writes to local memory are okay. This is fine for the purpose of nosync, but would e.g. prevent us from inferring nofree from readnone - which is slightly surprising.

Differential Revision: https://reviews.llvm.org/D99769

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[funcattrs] Infer nosync from readnone and non-convergent

This implements the most basic possible nosync inference. The choice of inference rule is taken from the comments in attributor and the disc

[funcattrs] Infer nosync from readnone and non-convergent

This implements the most basic possible nosync inference. The choice of inference rule is taken from the comments in attributor and the discussion on the review of the change which introduced the nosync attribute (0626367202c).

This is deliberately minimal. As noted in code comments, I do plan to add a more robust inference which actually scans the function IR directly, but a) I need to do some refactoring of the attributor code to use common interfaces, and b) I wanted to get something in. I also wanted to minimize the "interesting" analysis discussion since that's time intensive.

Context: This combines with existing nofree attribute inference to help prove dereferenceability in the ongoing deref-at-point semantics work.

Differential Revision: https://reviews.llvm.org/D99749

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[FunctionAttrs] Infer willreturn for functions without loops

If a function doesn't contain loops and does not call non-willreturn
functions, then it is willreturn. Loops are detected by checking
for

[FunctionAttrs] Infer willreturn for functions without loops

If a function doesn't contain loops and does not call non-willreturn
functions, then it is willreturn. Loops are detected by checking
for backedges in the function. We don't attempt to handle finite
loops at this point.

Differential Revision: https://reviews.llvm.org/D94633

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[IR] Make nosync, nofree and willreturn default for intrinsics.

D70365 allows us to make attributes default. This is a follow up to
actually make nosync, nofree and willreturn default. The approach

[IR] Make nosync, nofree and willreturn default for intrinsics.

D70365 allows us to make attributes default. This is a follow up to
actually make nosync, nofree and willreturn default. The approach we
chose, for now, is to opt-in to default attributes to avoid introducing
problems to target specific intrinsics. Intrinsics with default
attributes can be created using `DefaultAttrsIntrinsic` class.

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[FunctionAttrs] Rename functionattrs -> function-attrs

To match NewPM pass name, and also for readability.
Also rename rpo-functionattrs -> rpo-function-attrs while we're here.

Reviewed By: arsenm

[FunctionAttrs] Rename functionattrs -> function-attrs

To match NewPM pass name, and also for readability.
Also rename rpo-functionattrs -> rpo-function-attrs while we're here.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D84694

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[BasicAA] Rename deprecated -basicaa to -basic-aa

Follow-up to D82607
Revert an accidental change (empty.ll) of D82683

[FunctionAttrs] Annotate "willreturn" for intrinsics

Summary:
In D62801, new function attribute `willreturn` was introduced. In short, a function with `willreturn` is guaranteed to come back to the

[FunctionAttrs] Annotate "willreturn" for intrinsics

Summary:
In D62801, new function attribute `willreturn` was introduced. In short, a function with `willreturn` is guaranteed to come back to the call site(more precise definition is in LangRef).

In this patch, willreturn is annotated for LLVM intrinsics.

Reviewers: jdoerfert

Reviewed By: jdoerfert

Subscribers: jvesely, nhaehnle, sstefan1, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64904

llvm-svn: 367184

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Add, and infer, a nofree function attribute

This patch adds a function attribute, nofree, to indicate that a function does
not, directly or indirectly, call a memory-deallocation function (e.g., fre

Add, and infer, a nofree function attribute

This patch adds a function attribute, nofree, to indicate that a function does
not, directly or indirectly, call a memory-deallocation function (e.g., free,
C++'s operator delete).

Reviewers: jdoerfert

Differential Revision: https://reviews.llvm.org/D49165

llvm-svn: 365336

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[FunctionAttrs] Infer WriteOnly Function Attribute

These changes expand the FunctionAttr logic in order to mark functions as
WriteOnly when appropriate. This is done through an additional bool varia

[FunctionAttrs] Infer WriteOnly Function Attribute

These changes expand the FunctionAttr logic in order to mark functions as
WriteOnly when appropriate. This is done through an additional bool variable
and extended logic.

Reviewers: hfinkel, jdoerfert

Differential Revision: https://reviews.llvm.org/D48387

llvm-svn: 340537

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Remove alignment argument from memcpy/memmove/memset in favour of alignment attributes (Step 1)

Summary:
This is a resurrection of work first proposed and discussed in Aug 2015:
http://lists.llv

Remove alignment argument from memcpy/memmove/memset in favour of alignment attributes (Step 1)

Summary:
This is a resurrection of work first proposed and discussed in Aug 2015:
http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.html
and initially landed (but then backed out) in Nov 2015:
http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html

The @llvm.memcpy/memmove/memset intrinsics currently have an explicit argument
which is required to be a constant integer. It represents the alignment of the
dest (and source), and so must be the minimum of the actual alignment of the
two.

This change is the first in a series that allows source and dest to each
have their own alignments by using the alignment attribute on their arguments.

In this change we:
1) Remove the alignment argument.
2) Add alignment attributes to the source & dest arguments. We, temporarily,
require that the alignments for source & dest be equal.

For example, code which used to read:
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %src, i32 100, i32 4, i1 false)
will now read
call void @llvm.memcpy.p0i8.p0i8.i32(i8* align 4 %dest, i8* align 4 %src, i32 100, i1 false)

Downstream users may have to update their lit tests that check for
@llvm.memcpy/memmove/memset call/declaration patterns. The following extended sed script
may help with updating the majority of your tests, but it does not catch all possible
patterns so some manual checking and updating will be required.

s~declare void @llvm\.mem(set|cpy|move)\.p([^(]*)\((.*), i32, i1\)~declare void @llvm.mem\1.p\2(\3, i1)~g
s~call void @llvm\.memset\.p([^(]*)i8\(i8([^*]*)\* (.*), i8 (.*), i8 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.memset.p\1i8(i8\2* \3, i8 \4, i8 \5, i1 \6)~g
s~call void @llvm\.memset\.p([^(]*)i16\(i8([^*]*)\* (.*), i8 (.*), i16 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.memset.p\1i16(i8\2* \3, i8 \4, i16 \5, i1 \6)~g
s~call void @llvm\.memset\.p([^(]*)i32\(i8([^*]*)\* (.*), i8 (.*), i32 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.memset.p\1i32(i8\2* \3, i8 \4, i32 \5, i1 \6)~g
s~call void @llvm\.memset\.p([^(]*)i64\(i8([^*]*)\* (.*), i8 (.*), i64 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.memset.p\1i64(i8\2* \3, i8 \4, i64 \5, i1 \6)~g
s~call void @llvm\.memset\.p([^(]*)i128\(i8([^*]*)\* (.*), i8 (.*), i128 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.memset.p\1i128(i8\2* \3, i8 \4, i128 \5, i1 \6)~g
s~call void @llvm\.memset\.p([^(]*)i8\(i8([^*]*)\* (.*), i8 (.*), i8 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.memset.p\1i8(i8\2* align \6 \3, i8 \4, i8 \5, i1 \7)~g
s~call void @llvm\.memset\.p([^(]*)i16\(i8([^*]*)\* (.*), i8 (.*), i16 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.memset.p\1i16(i8\2* align \6 \3, i8 \4, i16 \5, i1 \7)~g
s~call void @llvm\.memset\.p([^(]*)i32\(i8([^*]*)\* (.*), i8 (.*), i32 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.memset.p\1i32(i8\2* align \6 \3, i8 \4, i32 \5, i1 \7)~g
s~call void @llvm\.memset\.p([^(]*)i64\(i8([^*]*)\* (.*), i8 (.*), i64 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.memset.p\1i64(i8\2* align \6 \3, i8 \4, i64 \5, i1 \7)~g
s~call void @llvm\.memset\.p([^(]*)i128\(i8([^*]*)\* (.*), i8 (.*), i128 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.memset.p\1i128(i8\2* align \6 \3, i8 \4, i128 \5, i1 \7)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i8\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i8 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.mem\1.p\2i8(i8\3* \4, i8\5* \6, i8 \7, i1 \8)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i16\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i16 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.mem\1.p\2i16(i8\3* \4, i8\5* \6, i16 \7, i1 \8)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i32\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i32 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.mem\1.p\2i32(i8\3* \4, i8\5* \6, i32 \7, i1 \8)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i64\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i64 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.mem\1.p\2i64(i8\3* \4, i8\5* \6, i64 \7, i1 \8)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i128\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i128 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.mem\1.p\2i128(i8\3* \4, i8\5* \6, i128 \7, i1 \8)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i8\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i8 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.mem\1.p\2i8(i8\3* align \8 \4, i8\5* align \8 \6, i8 \7, i1 \9)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i16\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i16 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.mem\1.p\2i16(i8\3* align \8 \4, i8\5* align \8 \6, i16 \7, i1 \9)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i32\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i32 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.mem\1.p\2i32(i8\3* align \8 \4, i8\5* align \8 \6, i32 \7, i1 \9)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i64\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i64 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.mem\1.p\2i64(i8\3* align \8 \4, i8\5* align \8 \6, i64 \7, i1 \9)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i128\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i128 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.mem\1.p\2i128(i8\3* align \8 \4, i8\5* align \8 \6, i128 \7, i1 \9)~g

The remaining changes in the series will:
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
source and dest alignments.
Step 3) Update Clang to use the new IRBuilder API.
Step 4) Update Polly to use the new IRBuilder API.
Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API,
and those that use use MemIntrinsicInst::[get|set]Alignment() to use
getDestAlignment() and getSourceAlignment() instead.
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
MemIntrinsicInst::[get|set]Alignment() methods.

Reviewers: pete, hfinkel, lhames, reames, bollu

Reviewed By: reames

Subscribers: niosHD, reames, jholewinski, qcolombet, jfb, sanjoy, arsenm, dschuff, dylanmckay, mehdi_amini, sdardis, nemanjai, david2050, nhaehnle, javed.absar, sbc100, jgravelle-google, eraman, aheejin, kbarton, JDevlieghere, asb, rbar, johnrusso, simoncook, jordy.potman.lists, apazos, sabuasal, llvm-commits

Differential Revision: https://reviews.llvm.org/D41675

llvm-svn: 322965

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[attrs] Move the norecurse deduction to operate on the node set rather
than the SCC object, and have it scan the instruction stream directly
rather than relying on call records.

This makes the behav

[attrs] Move the norecurse deduction to operate on the node set rather
than the SCC object, and have it scan the instruction stream directly
rather than relying on call records.

This makes the behavior of this routine consistent between libc routines
and LLVM intrinsics for libc routines. We can go and start teaching it
about those being norecurse, but we should behave the same for the
intrinsic and the libc routine rather than differently. I chatted with
James Molloy and the inconsistency doesn't seem intentional and likely
is due to intrinsic calls not being modelled in the call graph analyses.

This also fixes a bug where we would deduce norecurse on optnone
functions, when generally we try to handle optnone functions as-if they
were replaceable and thus unanalyzable.

llvm-svn: 260813

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Revert "Change memcpy/memset/memmove to have dest and source alignments."

This reverts commit r253511.

This likely broke the bots in
http://lab.llvm.org:8011/builders/clang-ppc64-elf-linux2/builds/

Revert "Change memcpy/memset/memmove to have dest and source alignments."

This reverts commit r253511.

This likely broke the bots in
http://lab.llvm.org:8011/builders/clang-ppc64-elf-linux2/builds/20202
http://bb.pgr.jp/builders/clang-3stage-i686-linux/builds/3787

llvm-svn: 253543

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Change memcpy/memset/memmove to have dest and source alignments.

Note, this was reviewed (and more details are in) http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html

Thes

Change memcpy/memset/memmove to have dest and source alignments.

Note, this was reviewed (and more details are in) http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html

These intrinsics currently have an explicit alignment argument which is
required to be a constant integer. It represents the alignment of the
source and dest, and so must be the minimum of those.

This change allows source and dest to each have their own alignments
by using the alignment attribute on their arguments. The alignment
argument itself is removed.

There are a few places in the code for which the code needs to be
checked by an expert as to whether using only src/dest alignment is
safe. For those places, they currently take the minimum of src/dest
alignments which matches the current behaviour.

For example, code which used to read:
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %src, i32 500, i32 8, i1 false)
will now read:
call void @llvm.memcpy.p0i8.p0i8.i32(i8* align 8 %dest, i8* align 8 %src, i32 500, i1 false)

For out of tree owners, I was able to strip alignment from calls using sed by replacing:
(call.*llvm\.memset.*)i32\ [0-9]*\,\ i1 false\)
with:
$1i1 false)

and similarly for memmove and memcpy.

I then added back in alignment to test cases which needed it.

A similar commit will be made to clang which actually has many differences in alignment as now
IRBuilder can generate different source/dest alignments on calls.

In IRBuilder itself, a new argument was added. Instead of calling:
CreateMemCpy(Dst, Src, getInt64(Size), DstAlign, /* isVolatile */ false)
you now call
CreateMemCpy(Dst, Src, getInt64(Size), DstAlign, SrcAlign, /* isVolatile */ false)

There is a temporary class (IntegerAlignment) which takes the source alignment and rejects
implicit conversion from bool. This is to prevent isVolatile here from passing its default
parameter to the source alignment.

Note, changes in future can now be made to codegen. I didn't change anything here, but this
change should enable better memcpy code sequences.

Reviewed by Hal Finkel.

llvm-svn: 253511

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Revert "Revert "[FunctionAttrs] Identify norecurse functions""

This reapplies this patch, with test fixes.

llvm-svn: 252871

Revert "[FunctionAttrs] Identify norecurse functions"

This reverts commit r252862. This introduced test failures and I'm reverting while I investigate how this happened.

llvm-svn: 252863