[DebugInfo][RemoveDIs] Handle dbg.declares in SelectionDAGISel (#73496)

This is a boring mechanical update to support DPValues that look like
dbg.declares in SelectionDAG.

The tests will become

[DebugInfo][RemoveDIs] Handle dbg.declares in SelectionDAGISel (#73496)

This is a boring mechanical update to support DPValues that look like
dbg.declares in SelectionDAG.

The tests will become "live" once #74090 lands (see for more info).

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[DebugInfo] Produce variadic DBG_INSTR_REFs from ISel

This patch modifies SelectionDAG and FastISel to produce DBG_INSTR_REFs with
variadic expressions, and produce DBG_INSTR_REFs for debug values w

[DebugInfo] Produce variadic DBG_INSTR_REFs from ISel

This patch modifies SelectionDAG and FastISel to produce DBG_INSTR_REFs with
variadic expressions, and produce DBG_INSTR_REFs for debug values with variadic
location expressions. The former essentially means just prepending
DW_OP_LLVM_arg, 0 to the existing expression. The latter is achieved in
MachineFunction::finalizeDebugInstrRefs and InstrEmitter::EmitDbgInstrRef.

Reviewed By: jmorse, Orlando

Differential Revision: https://reviews.llvm.org/D133929

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[DebugInfo] Convert most tests to opaque pointers (NFC)

Revert "[NFC] remove explicit default value for strboolattr attribute in tests"

This reverts commit bda6e5bee04c75b1f1332b4fd1ac4e8ef6c3c247.

See https://lab.llvm.org/buildbot/#/builders/109/builds

Revert "[NFC] remove explicit default value for strboolattr attribute in tests"

This reverts commit bda6e5bee04c75b1f1332b4fd1ac4e8ef6c3c247.

See https://lab.llvm.org/buildbot/#/builders/109/builds/15424 for instance

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[NFC] remove explicit default value for strboolattr attribute in tests

Since d6de1e1a71406c75a4ea4d5a2fe84289f07ea3a1, no attributes is quivalent to
setting attribute to false.

This is a preliminar

[NFC] remove explicit default value for strboolattr attribute in tests

Since d6de1e1a71406c75a4ea4d5a2fe84289f07ea3a1, no attributes is quivalent to
setting attribute to false.

This is a preliminary commit for https://reviews.llvm.org/D99080

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OpaquePtr: Bulk update tests to use typed byval

Upgrade of the IR text tests should be the only thing blocking making
typed byval mandatory. Partially done through regex and partially
manual.

Revert "[DebugInfo] Remove some users of DBG_VALUEs IsIndirect field"

This reverts commit ed29dbaafa49bb8c9039a35f768244c394411fea.

I'm backing out D68945, which as the discussion for D73526 shows,

Revert "[DebugInfo] Remove some users of DBG_VALUEs IsIndirect field"

This reverts commit ed29dbaafa49bb8c9039a35f768244c394411fea.

I'm backing out D68945, which as the discussion for D73526 shows, doesn't
seem to handle the -O0 path through the codegen backend correctly. I'll
reland the patch when a fix is worked out, apologies for all the churn.
The two parent commits are part of this revert too.

Conflicts:
llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
llvm/test/DebugInfo/X86/dbg-addr-dse.ll

SelectionDAGBuilder conflict is due to a nearby change in e39e2b4a79c6
that's technically unrelated. dbg-addr-dse.ll conflicted because
41206b61e30c (legitimately) changes the order of two lines.

There are further modifications to dbg-value-func-arg.ll: it landed after
the patch being reverted, and I've converted indirection to be represented
by the isIndirect field rather than DW_OP_deref.

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Revert "[SafeStack][DebugInfo] Insert DW_OP_deref in correct location"

This reverts commit 2d3174c4df6b5f4131346828d0a31675d80d6e2b.

The overall solution for this problem is reverting D68945, which

Revert "[SafeStack][DebugInfo] Insert DW_OP_deref in correct location"

This reverts commit 2d3174c4df6b5f4131346828d0a31675d80d6e2b.

The overall solution for this problem is reverting D68945, which wasn't
handling the -O0 path through the codegen backend correctly. See:
discussion in D73526.

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[SafeStack][DebugInfo] Insert DW_OP_deref in correct location

This patch addresses the issue found in https://bugs.llvm.org/show_bug.cgi?id=44585
where a DW_OP_deref was placed at the end of a dwarf

[SafeStack][DebugInfo] Insert DW_OP_deref in correct location

This patch addresses the issue found in https://bugs.llvm.org/show_bug.cgi?id=44585
where a DW_OP_deref was placed at the end of a dwarf expression, resulting in corrupt
symbols when debugging.

This is an attempt to reland with a few fixes for buildbot since I
haven't merged from master in a bit.

Differential Revision: https://reviews.llvm.org/D73526

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Revert "[SafeStack][DebugInfo] Insert DW_OP_deref in correct location"

This reverts commit fff6a1b0f1fe57b46379001db75952d2a06eab1f.

This was breaking a bunch of buildbots.

[SafeStack][DebugInfo] Insert DW_OP_deref in correct location

This patch addresses the issue found in https://bugs.llvm.org/show_bug.cgi?id=44585
where a DW_OP_deref was placed at the end of a dwarf

[SafeStack][DebugInfo] Insert DW_OP_deref in correct location

This patch addresses the issue found in https://bugs.llvm.org/show_bug.cgi?id=44585
where a DW_OP_deref was placed at the end of a dwarf expression, resulting in
corrupt symbols when debugging.

Differential Revision: https://reviews.llvm.org/D73526

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Migrate function attribute "no-frame-pointer-elim"="false" to "frame-pointer"="none" as cleanups after D56351

[DebugInfo] Remove some users of DBG_VALUEs IsIndirect field

This patch kills off a significant user of the "IsIndirect" field of
DBG_VALUE machine insts. Brought up in in PR41675, IsIndirect is
tec

[DebugInfo] Remove some users of DBG_VALUEs IsIndirect field

This patch kills off a significant user of the "IsIndirect" field of
DBG_VALUE machine insts. Brought up in in PR41675, IsIndirect is
techncally redundant as it can be expressed by the DIExpression of a
DBG_VALUE inst, and it isn't helpful to have two ways of expressing
things.

Rather than setting IsIndirect, have DBG_VALUE creators add an extra deref
to the insts DIExpression. There should now be no appearences of
IsIndirect=True from isel down to LiveDebugVariables / VirtRegRewriter,
which is ensured by an assertion in LDVImpl::handleDebugValue. This means
we also get to delete the IsIndirect handling in LiveDebugVariables. Tests
can be upgraded by for example swapping the following IsIndirect=True
DBG_VALUE:

DBG_VALUE $somereg, 0, !123, !DIExpression(DW_OP_foo)

With one where the indirection is in the DIExpression, by _appending_
a deref:

DBG_VALUE $somereg, $noreg, !123, !DIExpression(DW_OP_foo, DW_OP_deref)

Which both mean the same thing.

Most of the test changes in this patch are updates of that form; also some
changes in how the textual assembly printer handles these insts.

Differential Revision: https://reviews.llvm.org/D68945

llvm-svn: 374877

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Rename ExpandISelPseudo->FinalizeISel, delay register reservation

This allows targets to make more decisions about reserved registers
after isel. For example, now it should be certain there are call

Rename ExpandISelPseudo->FinalizeISel, delay register reservation

This allows targets to make more decisions about reserved registers
after isel. For example, now it should be certain there are calls or
stack objects in the frame or not, which could have been introduced by
legalization.

Patch by Matthias Braun

llvm-svn: 363757

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[DebugInfo] Add DILabel metadata and intrinsic llvm.dbg.label.

In order to set breakpoints on labels and list source code around
labels, we need collect debug information for labels, i.e., label
nam

[DebugInfo] Add DILabel metadata and intrinsic llvm.dbg.label.

In order to set breakpoints on labels and list source code around
labels, we need collect debug information for labels, i.e., label
name, the function label belong, line number in the file, and the
address label located. In order to keep these information in LLVM
IR and to allow backend to generate debug information correctly.
We create a new kind of metadata for labels, DILabel. The format
of DILabel is

!DILabel(scope: !1, name: "foo", file: !2, line: 3)

We hope to keep debug information as much as possible even the
code is optimized. So, we create a new kind of intrinsic for label
metadata to avoid the metadata is eliminated with basic block.
The intrinsic will keep existing if we keep it from optimized out.
The format of the intrinsic is

llvm.dbg.label(metadata !1)

It has only one argument, that is the DILabel metadata. The
intrinsic will follow the label immediately. Backend could get the
label metadata through the intrinsic's parameter.

We also create DIBuilder API for labels to be used by Frontend.
Frontend could use createLabel() to allocate DILabel objects, and use
insertLabel() to insert llvm.dbg.label intrinsic in LLVM IR.

Differential Revision: https://reviews.llvm.org/D45024

Patch by Hsiangkai Wang.

llvm-svn: 331841

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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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Parse and print DIExpressions inline to ease IR and MIR testing

Summary:
Most DIExpressions are empty or very simple. When they are complex, they
tend to be unique, so checking them inline is reason

Parse and print DIExpressions inline to ease IR and MIR testing

Summary:
Most DIExpressions are empty or very simple. When they are complex, they
tend to be unique, so checking them inline is reasonable.

This also avoids the need for CodeGen passes to append to the
llvm.dbg.mir named md node.

See also PR22780, for making DIExpression not be an MDNode.

Reviewers: aprantl, dexonsmith, dblaikie

Subscribers: qcolombet, javed.absar, eraman, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D37075

llvm-svn: 311594

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Remove the obsolete offset parameter from @llvm.dbg.value

There is no situation where this rarely-used argument cannot be
substituted with a DIExpression and removing it allows us to simplify
the DW

Remove the obsolete offset parameter from @llvm.dbg.value

There is no situation where this rarely-used argument cannot be
substituted with a DIExpression and removing it allows us to simplify
the DWARF backend. Note that this patch does not yet remove any of
the newly dead code.

rdar://problem/33580047
Differential Revision: https://reviews.llvm.org/D35951

llvm-svn: 309426

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Align definition of DW_OP_plus with DWARF spec [3/3]

Summary:
This patch is part of 3 patches that together form a single patch, but must be introduced in stages in order not to break things.

The

Align definition of DW_OP_plus with DWARF spec [3/3]

Summary:
This patch is part of 3 patches that together form a single patch, but must be introduced in stages in order not to break things.

The way that LLVM interprets DW_OP_plus in DIExpression nodes is basically that of the DW_OP_plus_uconst operator since LLVM expects an unsigned constant operand. This unnecessarily restricts the DW_OP_plus operator, preventing it from being used to describe the evaluation of runtime values on the expression stack. These patches try to align the semantics of DW_OP_plus and DW_OP_minus with that of the DWARF definition, which pops two elements off the expression stack, performs the operation and pushes the result back on the stack.

This is done in three stages:
• The first patch (LLVM) adds support for DW_OP_plus_uconst.
• The second patch (Clang) contains changes all its uses from DW_OP_plus to DW_OP_plus_uconst.
• The third patch (LLVM) changes the semantics of DW_OP_plus and DW_OP_minus to be in line with its DWARF meaning. This patch includes the bitcode upgrade from legacy DIExpressions.

Patch by Sander de Smalen.

Reviewers: echristo, pcc, aprantl

Reviewed By: aprantl

Subscribers: fhahn, javed.absar, aprantl, llvm-commits

Differential Revision: https://reviews.llvm.org/D33894

llvm-svn: 305386

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[MIR] Print on the given output instead of stderr.

Currently the MIR framework prints all its outputs (errors and actual
representation) on stderr.

This patch fixes that by printing the regular out

[MIR] Print on the given output instead of stderr.

Currently the MIR framework prints all its outputs (errors and actual
representation) on stderr.

This patch fixes that by printing the regular output in the output
specified with -o.

Differential Revision: http://reviews.llvm.org/D22251

llvm-svn: 275314

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DebugInfo: Remove MDString-based type references

Eliminate DITypeIdentifierMap and make DITypeRef a thin wrapper around
DIType*. It is no longer legal to refer to a DICompositeType by its
'identifi

DebugInfo: Remove MDString-based type references

Eliminate DITypeIdentifierMap and make DITypeRef a thin wrapper around
DIType*. It is no longer legal to refer to a DICompositeType by its
'identifier:', and DIBuilder no longer retains all types with an
'identifier:' automatically.

Aside from the bitcode upgrade, this is mainly removing logic to resolve
an MDString-based reference to an actualy DIType. The commits leading
up to this have made the implicit type map in DICompileUnit's
'retainedTypes:' field superfluous.

This does not remove DITypeRef, DIScopeRef, DINodeRef, and
DITypeRefArray, or stop using them in DI-related metadata. Although as
of this commit they aren't serving a useful purpose, there are patchces
under review to reuse them for CodeView support.

The tests in LLVM were updated with deref-typerefs.sh, which is attached
to the thread "[RFC] Lazy-loading of debug info metadata":

http://lists.llvm.org/pipermail/llvm-dev/2016-April/098318.html

llvm-svn: 267296

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[PR27284] Reverse the ownership between DICompileUnit and DISubprogram.

Currently each Function points to a DISubprogram and DISubprogram has a
scope field. For member functions the scope is a DICom

[PR27284] Reverse the ownership between DICompileUnit and DISubprogram.

Currently each Function points to a DISubprogram and DISubprogram has a
scope field. For member functions the scope is a DICompositeType. DIScopes
point to the DICompileUnit to facilitate type uniquing.

Distinct DISubprograms (with isDefinition: true) are not part of the type
hierarchy and cannot be uniqued. This change removes the subprograms
list from DICompileUnit and instead adds a pointer to the owning compile
unit to distinct DISubprograms. This would make it easy for ThinLTO to
strip unneeded DISubprograms and their transitively referenced debug info.

Motivation
----------

Materializing DISubprograms is currently the most expensive operation when
doing a ThinLTO build of clang.

We want the DISubprogram to be stored in a separate Bitcode block (or the
same block as the function body) so we can avoid having to expensively
deserialize all DISubprograms together with the global metadata. If a
function has been inlined into another subprogram we need to store a
reference the block containing the inlined subprogram.

Attached to https://llvm.org/bugs/show_bug.cgi?id=27284 is a python script
that updates LLVM IR testcases to the new format.

http://reviews.llvm.org/D19034
<rdar://problem/25256815>

llvm-svn: 266446

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testcase gardening: update the emissionKind enum to the new syntax. (NFC)

llvm-svn: 265081

When printing MIR, output to errs() rather than outs().

Summary:
Without this, this command

$ llvm-run llc -stop-after machine-cp -o - <( echo '' )

outputs an error, because we close stdout twic

When printing MIR, output to errs() rather than outs().

Summary:
Without this, this command

$ llvm-run llc -stop-after machine-cp -o - <( echo '' )

outputs an error, because we close stdout twice -- once when closing the
file opened for "-o", and again when closing outs().

Also clarify in the outs() definition that you can't ever call it if you
want to open your own raw_fd_ostream on stdout.

Reviewers: jroelofs, tstellarAMD

Subscribers: jholewinski, qcolombet, dsanders, llvm-commits

Differential Revision: http://reviews.llvm.org/D17422

llvm-svn: 261286

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llvm/test/DebugInfo/X86/safestack-byval.ll: Give an explicit triple for now. It crashes for targeting *-win32.

Also revert r254375 and r254361.

llvm-svn: 254397