History log of /llvm-project-15.0.7/llvm/test/Transforms/MemCpyOpt/capturing-func.ll (Results 1 – 17 of 17)
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Revision tags: llvmorg-20.1.0, llvmorg-20.1.0-rc3, llvmorg-20.1.0-rc2, llvmorg-20.1.0-rc1, llvmorg-21-init, llvmorg-19.1.7, llvmorg-19.1.6, llvmorg-19.1.5, llvmorg-19.1.4, llvmorg-19.1.3, llvmorg-19.1.2, llvmorg-19.1.1, llvmorg-19.1.0, llvmorg-19.1.0-rc4, llvmorg-19.1.0-rc3, llvmorg-19.1.0-rc2, llvmorg-19.1.0-rc1, llvmorg-20-init, llvmorg-18.1.8, llvmorg-18.1.7, llvmorg-18.1.6, llvmorg-18.1.5, llvmorg-18.1.4, llvmorg-18.1.3, llvmorg-18.1.2, llvmorg-18.1.1, llvmorg-18.1.0, llvmorg-18.1.0-rc4, llvmorg-18.1.0-rc3, llvmorg-18.1.0-rc2, llvmorg-18.1.0-rc1, llvmorg-19-init, llvmorg-17.0.6, llvmorg-17.0.5, llvmorg-17.0.4, llvmorg-17.0.3, llvmorg-17.0.2, llvmorg-17.0.1, llvmorg-17.0.0, llvmorg-17.0.0-rc4, llvmorg-17.0.0-rc3, llvmorg-17.0.0-rc2, llvmorg-17.0.0-rc1, llvmorg-18-init, llvmorg-16.0.6, llvmorg-16.0.5, llvmorg-16.0.4, llvmorg-16.0.3, llvmorg-16.0.2, llvmorg-16.0.1, llvmorg-16.0.0, llvmorg-16.0.0-rc4, llvmorg-16.0.0-rc3, llvmorg-16.0.0-rc2, llvmorg-16.0.0-rc1, llvmorg-17-init, llvmorg-15.0.7, llvmorg-15.0.6, llvmorg-15.0.5, llvmorg-15.0.4, llvmorg-15.0.3, llvmorg-15.0.2, llvmorg-15.0.1, llvmorg-15.0.0, llvmorg-15.0.0-rc3, llvmorg-15.0.0-rc2, llvmorg-15.0.0-rc1, llvmorg-16-init, llvmorg-14.0.6, llvmorg-14.0.5, llvmorg-14.0.4, llvmorg-14.0.3, llvmorg-14.0.2, llvmorg-14.0.1, llvmorg-14.0.0, llvmorg-14.0.0-rc4, llvmorg-14.0.0-rc3, llvmorg-14.0.0-rc2, llvmorg-14.0.0-rc1, llvmorg-15-init, llvmorg-13.0.1, llvmorg-13.0.1-rc3, llvmorg-13.0.1-rc2
# 0d20407d 05-Jan-2022 Nikita Popov <[email protected]>

Reapply [MemCpyOpt] Look through pointer casts when checking capture

This is a recommit of the patch without changes. The reason for
the revert has been addressed in D117679.

-----

The user scanni

Reapply [MemCpyOpt] Look through pointer casts when checking capture

This is a recommit of the patch without changes. The reason for
the revert has been addressed in D117679.

-----

The user scanning loop above looks through pointer casts, so we
also need to strip pointer casts in the capture check. Previously
the source was incorrectly considered not captured if a bitcast
was passed to the call.

show more ...


# 655a7024 13-Dec-2021 Nikita Popov <[email protected]>

Reapply [MemCpyOpt] Make capture check during call slot optimization more precise

This is a recommit of the patch without changes. The reason for
the revert has been addressed in D117679.

-----

Ca

Reapply [MemCpyOpt] Make capture check during call slot optimization more precise

This is a recommit of the patch without changes. The reason for
the revert has been addressed in D117679.

-----

Call slot optimization is currently supposed to be prevented if
the call can capture the source pointer. Due to an implementation
bug, this check currently doesn't trigger if a bitcast of the source
pointer is passed instead. I'm somewhat afraid of the fallout of
fixing this bug (due to heavy reliance on call slot optimization
in rust), so I'd like to strengthen the capture reasoning a bit first.

In particular, I believe that the capture is fine as long as a)
the call itself cannot depend on the pointer identity, because
neither dest has been captured before/at nor src before the
call and b) there is no potential use of the captured pointer
before the lifetime of the source alloca ends, either due to
lifetime.end or a return from a function. At that point the
potentially captured pointer becomes dangling.

Differential Revision: https://reviews.llvm.org/D115615

show more ...


# 53a51acc 18-Jan-2022 Hans Wennborg <[email protected]>

Revert "[MemCpyOpt] Make capture check during call slot optimization more precise"

This casued a miscompile due to call slot optimization replacing a call
argument without considering the call's !no

Revert "[MemCpyOpt] Make capture check during call slot optimization more precise"

This casued a miscompile due to call slot optimization replacing a call
argument without considering the call's !noalias metadata, see discussion on
the code review.

> Call slot optimization is currently supposed to be prevented if
> the call can capture the source pointer. Due to an implementation
> bug, this check currently doesn't trigger if a bitcast of the source
> pointer is passed instead. I'm somewhat afraid of the fallout of
> fixing this bug (due to heavy reliance on call slot optimization
> in rust), so I'd like to strengthen the capture reasoning a bit first.
>
> In particular, I believe that the capture is fine as long as a)
> the call itself cannot depend on the pointer identity, because
> neither dest has been captured before/at nor src before the
> call and b) there is no potential use of the captured pointer
> before the lifetime of the source alloca ends, either due to
> lifetime.end or a return from a function. At that point the
> potentially captured pointer becomes dangling.
>
> Differential Revision: https://reviews.llvm.org/D115615

Also reverting the dependent commit:

> [MemCpyOpt] Look through pointer casts when checking capture
>
> The user scanning loop above looks through pointer casts, so we
> also need to strip pointer casts in the capture check. Previously
> the source was incorrectly considered not captured if a bitcast
> was passed to the call.

This reverts commit 487a34ed9d7d24a7b1fb388c8856c784a459b22b
and 00e6869463ae6023d0d48f30de8511d6d748b14f.

show more ...


# 00e68694 05-Jan-2022 Nikita Popov <[email protected]>

[MemCpyOpt] Look through pointer casts when checking capture

The user scanning loop above looks through pointer casts, so we
also need to strip pointer casts in the capture check. Previously
the sou

[MemCpyOpt] Look through pointer casts when checking capture

The user scanning loop above looks through pointer casts, so we
also need to strip pointer casts in the capture check. Previously
the source was incorrectly considered not captured if a bitcast
was passed to the call.

show more ...


# 487a34ed 13-Dec-2021 Nikita Popov <[email protected]>

[MemCpyOpt] Make capture check during call slot optimization more precise

Call slot optimization is currently supposed to be prevented if
the call can capture the source pointer. Due to an implement

[MemCpyOpt] Make capture check during call slot optimization more precise

Call slot optimization is currently supposed to be prevented if
the call can capture the source pointer. Due to an implementation
bug, this check currently doesn't trigger if a bitcast of the source
pointer is passed instead. I'm somewhat afraid of the fallout of
fixing this bug (due to heavy reliance on call slot optimization
in rust), so I'd like to strengthen the capture reasoning a bit first.

In particular, I believe that the capture is fine as long as a)
the call itself cannot depend on the pointer identity, because
neither dest has been captured before/at nor src before the
call and b) there is no potential use of the captured pointer
before the lifetime of the source alloca ends, either due to
lifetime.end or a return from a function. At that point the
potentially captured pointer becomes dangling.

Differential Revision: https://reviews.llvm.org/D115615

show more ...


# c2e77c91 05-Jan-2022 Nikita Popov <[email protected]>

[MemCpyOpt] Add additional call slot capture tests (NFC)


# 396370e8 13-Dec-2021 Nikita Popov <[email protected]>

[MemCpyOpt] Add additional call slot capture tests (NFC)

One test shows a miscompile when bitcasts are involved, the others
cases where we can perform the optimization despite a capture.


Revision tags: llvmorg-13.0.1-rc1, llvmorg-13.0.0, llvmorg-13.0.0-rc4, llvmorg-13.0.0-rc3, llvmorg-13.0.0-rc2, llvmorg-13.0.0-rc1, llvmorg-14-init, llvmorg-12.0.1, llvmorg-12.0.1-rc4, llvmorg-12.0.1-rc3, llvmorg-12.0.1-rc2, llvmorg-12.0.1-rc1
# 88003cea 08-May-2021 Nikita Popov <[email protected]>

[MemCpyOpt] Remove MemDepAnalysis-based implementation

The MemorySSA-based implementation has been enabled for a few months
(since D94376). This patch drops the old MDA-based implementation
entirely

[MemCpyOpt] Remove MemDepAnalysis-based implementation

The MemorySSA-based implementation has been enabled for a few months
(since D94376). This patch drops the old MDA-based implementation
entirely.

I've kept this to only the basic cleanup of dropping various
conditions -- the code could be further cleaned up now that there
is only one implementation.

Differential Revision: https://reviews.llvm.org/D102113

show more ...


Revision tags: llvmorg-12.0.0, llvmorg-12.0.0-rc5, llvmorg-12.0.0-rc4, llvmorg-12.0.0-rc3, llvmorg-12.0.0-rc2, llvmorg-11.1.0, llvmorg-11.1.0-rc3, llvmorg-12.0.0-rc1, llvmorg-13-init, llvmorg-11.1.0-rc2, llvmorg-11.1.0-rc1, llvmorg-11.0.1, llvmorg-11.0.1-rc2, llvmorg-11.0.1-rc1
# d2f8961b 09-Nov-2020 Simon Pilgrim <[email protected]>

[MemCpyOpt] Remove unused check-prefixes

Just use default CHECK


Revision tags: llvmorg-11.0.0, llvmorg-11.0.0-rc6
# cd6f40f4 02-Oct-2020 Nikita Popov <[email protected]>

[MemCpyOpt] Add test scaffolding for MSSA based MemCpyOpt

This adds an -enable-memcpyopt-memoryssa option that currently does
nothing apart from requiring MSSA as a dependency. The tests are
split t

[MemCpyOpt] Add test scaffolding for MSSA based MemCpyOpt

This adds an -enable-memcpyopt-memoryssa option that currently does
nothing apart from requiring MSSA as a dependency. The tests are
split to run both with the option disabled and enabled. I went with
this rather than the separate directory DSE uses, as I found it
convenient to have a direct side-by-side comparison of differences.

Differential Revision: https://reviews.llvm.org/D89206

show more ...


# 64c54c54 01-Oct-2020 Nikita Popov <[email protected]>

[MemCpyOpt] Regnerate test checks (NFC)


Revision tags: llvmorg-11.0.0-rc5, llvmorg-11.0.0-rc4, llvmorg-11.0.0-rc3, llvmorg-11.0.0-rc2, llvmorg-11.0.0-rc1, llvmorg-12-init, llvmorg-10.0.1, llvmorg-10.0.1-rc4, llvmorg-10.0.1-rc3
# f31811f2 27-Jun-2020 Fangrui Song <[email protected]>

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

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


Revision tags: llvmorg-10.0.1-rc2, llvmorg-10.0.1-rc1, llvmorg-10.0.0, llvmorg-10.0.0-rc6, llvmorg-10.0.0-rc5, llvmorg-10.0.0-rc4, llvmorg-10.0.0-rc3, llvmorg-10.0.0-rc2, llvmorg-10.0.0-rc1, llvmorg-11-init, llvmorg-9.0.1, llvmorg-9.0.1-rc3, llvmorg-9.0.1-rc2, llvmorg-9.0.1-rc1, llvmorg-9.0.0, llvmorg-9.0.0-rc6, llvmorg-9.0.0-rc5, llvmorg-9.0.0-rc4, llvmorg-9.0.0-rc3, llvmorg-9.0.0-rc2, llvmorg-9.0.0-rc1, llvmorg-10-init, llvmorg-8.0.1, llvmorg-8.0.1-rc4, llvmorg-8.0.1-rc3, llvmorg-8.0.1-rc2, llvmorg-8.0.1-rc1
# cee313d2 17-Apr-2019 Eric Christopher <[email protected]>

Revert "Temporarily Revert "Add basic loop fusion pass.""

The reversion apparently deleted the test/Transforms directory.

Will be re-reverting again.

llvm-svn: 358552


Revision tags: llvmorg-8.0.0, llvmorg-8.0.0-rc5, llvmorg-8.0.0-rc4, llvmorg-8.0.0-rc3, llvmorg-7.1.0, llvmorg-7.1.0-rc1, llvmorg-8.0.0-rc2, llvmorg-8.0.0-rc1, llvmorg-7.0.1, llvmorg-7.0.1-rc3, llvmorg-7.0.1-rc2, llvmorg-7.0.1-rc1, llvmorg-7.0.0, llvmorg-7.0.0-rc3, llvmorg-7.0.0-rc2, llvmorg-7.0.0-rc1, llvmorg-6.0.1, llvmorg-6.0.1-rc3, llvmorg-6.0.1-rc2, llvmorg-6.0.1-rc1, llvmorg-5.0.2, llvmorg-5.0.2-rc2, llvmorg-5.0.2-rc1, llvmorg-6.0.0, llvmorg-6.0.0-rc3, llvmorg-6.0.0-rc2
# 1e68724d 19-Jan-2018 Daniel Neilson <[email protected]>

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

show more ...


Revision tags: llvmorg-6.0.0-rc1, llvmorg-5.0.1, llvmorg-5.0.1-rc3, llvmorg-5.0.1-rc2, llvmorg-5.0.1-rc1, llvmorg-5.0.0, llvmorg-5.0.0-rc5, llvmorg-5.0.0-rc4, llvmorg-5.0.0-rc3, llvmorg-5.0.0-rc2, llvmorg-5.0.0-rc1, llvmorg-4.0.1, llvmorg-4.0.1-rc3, llvmorg-4.0.1-rc2, llvmorg-4.0.1-rc1, llvmorg-4.0.0, llvmorg-4.0.0-rc4, llvmorg-4.0.0-rc3, llvmorg-4.0.0-rc2, llvmorg-4.0.0-rc1, llvmorg-3.9.1, llvmorg-3.9.1-rc3, llvmorg-3.9.1-rc2, llvmorg-3.9.1-rc1, llvmorg-3.9.0, llvmorg-3.9.0-rc3, llvmorg-3.9.0-rc2, llvmorg-3.9.0-rc1, llvmorg-3.8.1, llvmorg-3.8.1-rc1, llvmorg-3.8.0, llvmorg-3.8.0-rc3, llvmorg-3.8.0-rc2, llvmorg-3.8.0-rc1, llvmorg-3.7.1, llvmorg-3.7.1-rc2
# 67cf9a72 19-Nov-2015 Pete Cooper <[email protected]>

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

show more ...


# 72bc23ef 18-Nov-2015 Pete Cooper <[email protected]>

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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Revision tags: llvmorg-3.7.1-rc1, llvmorg-3.7.0, llvmorg-3.7.0-rc4, llvmorg-3.7.0-rc3, llvmorg-3.7.0-rc2, llvmorg-3.7.0-rc1, llvmorg-3.6.2, llvmorg-3.6.2-rc1, llvmorg-3.6.1, llvmorg-3.6.1-rc1, llvmorg-3.5.2, llvmorg-3.5.2-rc1, llvmorg-3.6.0, llvmorg-3.6.0-rc4, llvmorg-3.6.0-rc3, llvmorg-3.6.0-rc2, llvmorg-3.6.0-rc1, llvmorg-3.5.1, llvmorg-3.5.1-rc2, llvmorg-3.5.1-rc1, llvmorg-3.5.0, llvmorg-3.5.0-rc4, llvmorg-3.5.0-rc3, llvmorg-3.5.0-rc2, llvmorg-3.5.0-rc1
# 703e488e 14-Jul-2014 Nick Lewycky <[email protected]>

Don't eliminate memcpy's when the address of the pointer may itself be relevant. Fixes PR18304. Patch by David Wiberg!

llvm-svn: 212970