Revert "Cleanup codegen includes"

This reverts commit 7f230feeeac8a67b335f52bd2e900a05c6098f20.
Breaks CodeGenCUDA/link-device-bitcode.cu in check-clang,
and many LLVM tests, see comments on https:/

Revert "Cleanup codegen includes"

This reverts commit 7f230feeeac8a67b335f52bd2e900a05c6098f20.
Breaks CodeGenCUDA/link-device-bitcode.cu in check-clang,
and many LLVM tests, see comments on https://reviews.llvm.org/D121169

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Cleanup codegen includes

after: 1061034926
before: 1063332844

Differential Revision: https://reviews.llvm.org/D121169

[DebugInfo][InstrRef][NFC] Use unique_ptr instead of raw pointers

InstrRefBasedLDV allocates some big tables of ValueIDNum, to store live-in
and live-out block values in, that then get passed around

[DebugInfo][InstrRef][NFC] Use unique_ptr instead of raw pointers

InstrRefBasedLDV allocates some big tables of ValueIDNum, to store live-in
and live-out block values in, that then get passed around as pointers
everywhere. This patch wraps the allocation in a std::unique_ptr, names
some types based on unique_ptr, and passes references to those around
instead. There's no functional change, but it makes it clearer to the
reader that references to these tables are borrowed rather than owned, and
we get some extra validity assertions too.

Differential Revision: https://reviews.llvm.org/D118774

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Re-apply 3fab2d138e30, now with a triple added

Was reverted in 1c1b670a73a9 as it broke all non-x86 bots. Original commit
message:

[DebugInfo][InstrRef] Add a max-stack-slots-to-track cut-out

In

Re-apply 3fab2d138e30, now with a triple added

Was reverted in 1c1b670a73a9 as it broke all non-x86 bots. Original commit
message:

[DebugInfo][InstrRef] Add a max-stack-slots-to-track cut-out

In certain circumstances with things like autogenerated code and asan, you
can end up with thousands of Values live at the same time, causing a large
working set and a lot of information spilled to the stack. Unfortunately
InstrRefBasedLDV doesn't cope well with this and consumes a lot of memory
when there are many many stack slots. See the reproducer in D116821.

It seems very unlikely that a developer would be able to reason about
hundreds of live named local variables at the same time, so a huge working
set and many stack slots is an indicator that we're likely analysing
autogenerated or instrumented code. In those cases: gracefully degrade by
setting an upper bound on the amount of stack slots to track. This limits
peak memory consumption, at the cost of dropping some variable locations,
but in a rare scenario where it's unlikely someone is actually going to
use them.

In terms of the patch, this adds a cl::opt for max number of stack slots to
track, and has the stack-slot-numbering code optionally return None. That
then filters through a number of code paths, which can then chose to not
track a spill / restore if it touches an untracked spill slot. The added
test checks that we drop variable locations that are on the stack, if we
set the limit to zero.

Differential Revision: https://reviews.llvm.org/D118601

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Revert "[DebugInfo][InstrRef] Add a max-stack-slots-to-track cut-out"

This reverts commit 3fab2d138e30c65249e1eaea6cc68b2b7f50955a.

Breaking PPC sanitizer build:
https://lab.llvm.org/buildbot/#/bui

Revert "[DebugInfo][InstrRef] Add a max-stack-slots-to-track cut-out"

This reverts commit 3fab2d138e30c65249e1eaea6cc68b2b7f50955a.

Breaking PPC sanitizer build:
https://lab.llvm.org/buildbot/#/builders/105/builds/20857

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[DebugInfo][InstrRef] Add a max-stack-slots-to-track cut-out

In certain circumstances with things like autogenerated code and asan, you
can end up with thousands of Values live at the same time, cau

[DebugInfo][InstrRef] Add a max-stack-slots-to-track cut-out

In certain circumstances with things like autogenerated code and asan, you
can end up with thousands of Values live at the same time, causing a large
working set and a lot of information spilled to the stack. Unfortunately
InstrRefBasedLDV doesn't cope well with this and consumes a lot of memory
when there are many many stack slots. See the reproducer in D116821.

It seems very unlikely that a developer would be able to reason about
hundreds of live named local variables at the same time, so a huge working
set and many stack slots is an indicator that we're likely analysing
autogenerated or instrumented code. In those cases: gracefully degrade by
setting an upper bound on the amount of stack slots to track. This limits
peak memory consumption, at the cost of dropping some variable locations,
but in a rare scenario where it's unlikely someone is actually going to
use them.

In terms of the patch, this adds a cl::opt for max number of stack slots to
track, and has the stack-slot-numbering code optionally return None. That
then filters through a number of code paths, which can then chose to not
track a spill / restore if it touches an untracked spill slot. The added
test checks that we drop variable locations that are on the stack, if we
set the limit to zero.

Differential Revision: https://reviews.llvm.org/D118601

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[DebugInfo][InstrRef] Avoid dropping fragment info during PHI elimination

InstrRefBasedLDV used to crash on the added test -- the exit block is not
in scope for the variable being propagated, but is

[DebugInfo][InstrRef] Avoid dropping fragment info during PHI elimination

InstrRefBasedLDV used to crash on the added test -- the exit block is not
in scope for the variable being propagated, but is still considered because
it contains an assignment. The failure-mode was vlocJoin ignoring
assign-only blocks and not updating DIExpressions, but pickVPHILoc would
still find a variable location for it. That led to DBG_VALUEs created with
the wrong fragment information.

Fix this by removing a filter inherited from VarLocBasedLDV: vlocJoin will
now consider assign-only blocks and will update their expressions.

Differential Revision: https://reviews.llvm.org/D114727

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[DebugInfo][InstrRef] Terminate overlapping variable fragments

If we have a variable where its fragments are split into overlapping
segments:

DBG_VALUE $ax, $noreg, !123, !DIExpression(DW_OP_LL

[DebugInfo][InstrRef] Terminate overlapping variable fragments

If we have a variable where its fragments are split into overlapping
segments:

DBG_VALUE $ax, $noreg, !123, !DIExpression(DW_OP_LLVM_fragment_0, 16)
...
DBG_VALUE $eax, $noreg, !123, !DIExpression(DW_OP_LLVM_fragment_0, 32)

we should only propagate the most recently assigned fragment out of a
block. LiveDebugValues only deals with live-in variable locations, as
overlaps within blocks is DbgEntityHistoryCalculators domain.

InstrRefBasedLDV has kept the accumulateFragmentMap method from
VarLocBasedLDV, we just need it to recognise DBG_INSTR_REFs. Once it's
produced a mapping of variable / fragments to the overlapped variable /
fragments, VLocTracker uses it to identify when a debug instruction needs
to terminate the other parts it overlaps with. The test is updated for
some standard "InstrRef picks different registers" variation, and the
order of some unrelated DBG_VALUEs changes.

Differential Revision: https://reviews.llvm.org/D114603

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[X86] Update RET/LRET instruction to use the same naming convention as IRET (PR36876). NFC

Be more consistent in the naming convention for the various RET instructions to specify in terms of bitwidt

[X86] Update RET/LRET instruction to use the same naming convention as IRET (PR36876). NFC

Be more consistent in the naming convention for the various RET instructions to specify in terms of bitwidth.

Helps prevent future scheduler model mismatches like those that were only addressed in D44687.

Differential Revision: https://reviews.llvm.org/D113302

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[DebugInfo][NFC] Initialize a new object field in unittests

Over in e7084ceab3122 the InstrRefBasedLDV class grew a MachineRegisterInfo
pointer to lookup register sizes -- however, that field wasn't

[DebugInfo][NFC] Initialize a new object field in unittests

Over in e7084ceab3122 the InstrRefBasedLDV class grew a MachineRegisterInfo
pointer to lookup register sizes -- however, that field wasn't initialized
in the corresponding unit tests. This patch initializes it!

Fixes a buildbot failure reported on D112006

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[DebugInfo][InstrRef][NFC] Switch to using DenseMaps and similar

There are a few STL containers hanging around that can become DenseMaps,
SmallVectors and similar. This recovers a modest amount of c

[DebugInfo][InstrRef][NFC] Switch to using DenseMaps and similar

There are a few STL containers hanging around that can become DenseMaps,
SmallVectors and similar. This recovers a modest amount of compile time
performance.

While I'm here, adjust the bit layout of ValueIDNum: this was always
supposed to act like a value type, however it seems that clang doesn't
compile the comparison functions to act that way. Add a uint64_t to a
union that explicitly aliases the bitfields, so that we can compare the
whole value as a single integer.

Differential Revision: https://reviews.llvm.org/D112333

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[DebugInfo][InstrRef] Recover stack-slot tracking performance

This patch is like D111627 -- instead of calculating IDF for every location
on the stack, only do it for the smallest units of interfere

[DebugInfo][InstrRef] Recover stack-slot tracking performance

This patch is like D111627 -- instead of calculating IDF for every location
on the stack, only do it for the smallest units of interference, and copy
the PHIs for those units to any aliases.

The test added runs placeMLocPHIs directly, and tests that:
* A def of the lower 8 bits of a stack slot causes all aliasing regs to
have PHIs placed,
* It doesn't cause the equivalent location to x86's $ah, which isn't
aliased, to have a PHI placed.

Differential Revision: https://reviews.llvm.org/D112324

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[DebugInfo][Instr] Track subregisters across stack spills/restores

Sometimes we generate code that writes to a subregister, then spills /
restores a super-register to the stack, for example:

$e

[DebugInfo][Instr] Track subregisters across stack spills/restores

Sometimes we generate code that writes to a subregister, then spills /
restores a super-register to the stack, for example:

$eax = MOV32ri 0
MOV64mr $rsp, 1, $noreg, 16, $noreg, $rax
$rcx = MOV64rm $rsp, 1, $noreg, 8, $noreg

This patch takes a different approach: it adds another index to
MLocTracker that identifies a size/offset within a stack slot. A location
on the stack is then a pari of {FrameIndex, SlotNum}. Spilling and
restoring now involves pairing up the src/dest register numbers, and the
dest/src stack position to be transferred to/from. Location coverage
improves as a result, compile-time performance decreases, alas.

One limitation is that if a PHI occurs inside a stack slot:

DBG_PHI %stack.0, 1

We don't know how large the resulting value is, and so might have
difficulty picking which value to use. DBG_PHI might need to be augmented
in the future with such a size.

Unit tests added ensure that spills and restores correctly transfer to
positions in the Location => Value map, and that different register classes
written to the stack will correctly clobber all other positions in the
stack slot.

Differential Revision: https://reviews.llvm.org/D112133

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[DebugInfo][InstrRef] Add unit tests for transfer-function building

This patch adds some unit tests for the machine-location transfer-function
building parts of InstrRefBasedLDV: i.e., test that if

[DebugInfo][InstrRef] Add unit tests for transfer-function building

This patch adds some unit tests for the machine-location transfer-function
building parts of InstrRefBasedLDV: i.e., test that if we feed some MIR
into the transfer-function building code, does it create the correct
transfer function.

There are a number of minor defects that get corrected in the process:
* The unit test was selecting the x86 (i.e. 32 bit) backend rather than
x86_64's 64 bit backend,
* COPY instructions weren't actually having their subregister values
correctly represented in the transfer function. Subregisters were being
defined by the COPY, rather than taking the value in the source register.
* SP aliases were at risk of being clobbered, if an SP subregister was
clobbered.

Differential Revision: https://reviews.llvm.org/D112006

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[DebugInfo][InstrRef] Track a single variable at a time

Here's another performance patch for InstrRefBasedLDV: rather than
processing all variable values in a scope at a time, instead, process one
v

[DebugInfo][InstrRef] Track a single variable at a time

Here's another performance patch for InstrRefBasedLDV: rather than
processing all variable values in a scope at a time, instead, process one
variable at a time. The benefits are twofold:
* It's easier to reason about one variable at a time in your mind,
* It improves performance, apparently from increased locality.

The downside is that the value-propagation code gets indented one level
further, plus there's some churn in the unit tests.

Differential Revision: https://reviews.llvm.org/D111799

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[DebugInfo][InstrRef] Avoid un-necessary densemap copies and comparisons

This is purely a performance patch: InstrRefBasedLDV used to use three
DenseMaps to store variable values, two for long term

[DebugInfo][InstrRef] Avoid un-necessary densemap copies and comparisons

This is purely a performance patch: InstrRefBasedLDV used to use three
DenseMaps to store variable values, two for long term storage and one as a
working set. This patch eliminates the working set, and updates the long
term storage in place, thus avoiding two DenseMap comparisons and two
DenseMap assignments, which can be expensive.

Differential Revision: https://reviews.llvm.org/D111716

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[DebugInfo][InstrRef] Fix Wdangling-else warning in InstrRefLDVTest

Fix a dangling else that gcc-11 warned about. The EXPECT_EQ macro
expands to an if-else, so the whole construction contains a hidd

[DebugInfo][InstrRef] Fix Wdangling-else warning in InstrRefLDVTest

Fix a dangling else that gcc-11 warned about. The EXPECT_EQ macro
expands to an if-else, so the whole construction contains a hidden
dangling else.

Differential Revision: https://reviews.llvm.org/D112044

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[DebugInfo][InstrRef] Place variable-values PHI using LLVM utilities

This patch is very similar to D110173 / a3936a6c19c, but for variable
values rather than machine values. This is for the second i

[DebugInfo][InstrRef] Place variable-values PHI using LLVM utilities

This patch is very similar to D110173 / a3936a6c19c, but for variable
values rather than machine values. This is for the second instr-ref
problem, calculating the correct variable value on entry to each block.
The previous lattice based implementation was broken; we now use LLVMs
existing PHI placement utilities to work out where values need to merge,
then eliminate un-necessary ones through value propagation.

Most of the deletions here happen in vlocJoin: it was trying to pick a
location for PHIs to happen in, badly, leading to an infinite loop in the
MIR test added, where it would repeatedly switch between register
locations. The new approach is simpler: either PHIs can be eliminated, or
they can't, and the location of the value is a different problem.

Various bits and pieces move to the header so that they can be tested in
the unit tests. The DbgValue class grows a "VPHI" kind to represent
variable value PHIS that haven't been eliminated yet.

Differential Revision: https://reviews.llvm.org/D110630

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[DebugInfo][InstrRef] Use PHI placement utilities for machine locations

InstrRefBasedLDV used to try and determine which values are in which
registers using a lattice approach; however this is hard

[DebugInfo][InstrRef] Use PHI placement utilities for machine locations

InstrRefBasedLDV used to try and determine which values are in which
registers using a lattice approach; however this is hard to understand, and
broken in various ways. This patch replaces that approach with a standard
SSA approach using existing LLVM utilities. PHIs are placed at dominance
frontiers; value propagation then eliminates un-necessary PHIs.

This patch also adds a bunch of unit tests that should cover many of the
weirder forms of control flow.

Differential Revision: https://reviews.llvm.org/D110173

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[DebugInfo][NFC] Move LiveDebugValues class to header

This patch shifts the InstrRefBasedLDV class declaration to a header.
Partially because it's already massive, but mostly so that I can start
wri

[DebugInfo][NFC] Move LiveDebugValues class to header

This patch shifts the InstrRefBasedLDV class declaration to a header.
Partially because it's already massive, but mostly so that I can start
writing some unit tests for it. This patch also adds the boilerplate for
said unit tests.

Differential Revision: https://reviews.llvm.org/D110165

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