[WebAssembly] Fix register use-def in FixIrreducibleControlFlow

FixIrreducibleControlFlow pass adds dispatch blocks with a `br_table`
that has multiple predecessors and successors, because it serves

[WebAssembly] Fix register use-def in FixIrreducibleControlFlow

FixIrreducibleControlFlow pass adds dispatch blocks with a `br_table`
that has multiple predecessors and successors, because it serves as
something like a traffic hub for BBs. As a result of this, there can be
register uses that are not dominated by a def in every path from the
entry block. For example, suppose register %a is defined in BB1 and used
in BB2, and there is a single path from BB1 and BB2:
```
BB1 -> ... -> BB2
```
After FixIrreducibleControlFlow runs, there can be a dispatch block
between these two BBs:
```
BB1 -> ... -> Dispatch -> ... -> BB2
```
And this dispatch block has multiple predecessors, now
there is a path to BB2 that does not first visit BB1, and in that path
%a is not dominated by a def anymore.

To fix this problem, we have been adding `IMPLICIT_DEF`s to all
registers in PrepareForLiveInternals pass, and then remove unnecessary
ones in OptimizeLiveIntervals pass after computing `LiveIntervals`. But
FixIrreducibleControlFlow pass itself ends up violating register use-def
relationship, resulting in invalid code. This was OK so far because
MIR verifier apparently didn't check this in validation. But @arsenm
fixed this and it caught this bug in validation
(https://github.com/llvm/llvm-project/issues/55249).

This CL moves the `IMPLICIT_DEF` adding routine from
PrepareForLiveInternals to FixIrreducibleControlFlow. We only run it
when FixIrreducibleControlFlow changes the code. And then
PrepareForLiveInternals doesn't do anything other than setting
`TracksLiveness` property, which is a prerequisite for running
`LiveIntervals` analysis, which is required by the next pass
OptimizeLiveIntervals.

But in our backend we don't seem to do anything that invalidates this up
until OptimizeLiveIntervals, and I'm not sure why we are calling
`invalidateLiveness` in ReplacePhysRegs pass, because what that pass
does is to replace physical registers with virtual ones 1-to-1. I
deleted the `invalidateLiveness` call there and we don't need to set
that flag explicitly, which obviates all the need for
PrepareForLiveInternals.

(By the way, This 'Liveness' here is different from `LiveIntervals`
analysis. Setting this only means BBs' live-in info is correct, all uses
are dominated by defs, `kill` flag is conservatively correct, which
means if there is a `kill` flag set it should be the last use. See
https://github.com/llvm/llvm-project/blob/2a0837aab1489c88efb03784e34c4dc9f2e28302/llvm/include/llvm/CodeGen/MachineFunction.h#L125-L134
for details.)

So this CL removes PrepareForLiveInternals pass altogether. Something
similar to this was attempted by D56091 long ago but that came short of
actually removing the pass, and I couldn't land it because
FixIrreducibleControlFlow violated use-def relationship, which this CL
fixes.

This doesn't change output in any meaningful way. All test changes
except `irreducible-cfg.mir` are register numbering.

Also this will likely to reduce compilation time, because we have been
adding `IMPLICIT_DEF` for all registers every time `-O2` is given, but
now we do that only when there is irreducible control flow, which is
rare.

Fixes https://github.com/llvm/llvm-project/issues/55249.

Reviewed By: dschuff, kripken

Differential Revision: https://reviews.llvm.org/D125515

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[WebAssembly] Remove datalayout strings from llc tests

The data layout strings do not have any effect on llc tests and will become
misleadingly out of date as we continue to update the canonical dat

[WebAssembly] Remove datalayout strings from llc tests

The data layout strings do not have any effect on llc tests and will become
misleadingly out of date as we continue to update the canonical data layout, so
remove them from the tests.

Differential Revision: https://reviews.llvm.org/D105842

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[DAGCombiner] Rebuild (setcc x, y, ==) from (xor (xor x, y), 1)

The existing code already considered this case. Unfortunately a typo in
the condition prevents it from triggering. Also the existing c

[DAGCombiner] Rebuild (setcc x, y, ==) from (xor (xor x, y), 1)

The existing code already considered this case. Unfortunately a typo in
the condition prevents it from triggering. Also the existing code, had
it run, forgot to do the folding.

This fixes PR42876.

Differential Revision: https://reviews.llvm.org/D65802

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[WebAssembly] Replace all calls with generalized multivalue calls

Summary:
Extends the multivalue call infrastructure to tail calls, removes all
legacy calls specialized for particular result types,

[WebAssembly] Replace all calls with generalized multivalue calls

Summary:
Extends the multivalue call infrastructure to tail calls, removes all
legacy calls specialized for particular result types, and removes the
CallIndirectFixup pass, since all indirect call arguments are now
fixed up directly in the post-insertion hook.

In order to keep supporting pretty-printed defs and uses in test
expectations, MCInstLower now inserts an immediate containing the
number of defs for each call and call_indirect. The InstPrinter is
updated to query this immediate if it is present and determine which
MCOperands are defs and uses accordingly.

Depends on D72902.

Reviewers: aheejin

Subscribers: dschuff, mgorny, sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D74192

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[WebAssembly] Assembler/InstPrinter: support call_indirect type index.

A TYPE_INDEX operand (as used by call_indirect) used to be represented
by the InstPrinter as a symbol (e.g. .Ltype_index0@TYPE_

[WebAssembly] Assembler/InstPrinter: support call_indirect type index.

A TYPE_INDEX operand (as used by call_indirect) used to be represented
by the InstPrinter as a symbol (e.g. .Ltype_index0@TYPE_INDEX) which
was a bit of a mismatch with the WasmObjectWriter which expects an
unnamed symbol, to receive the signature from and then turn into a
reloc.

There was really no good way to round-trip this information. An earlier
version of this patch tried to attach the signature information using
a .functype, but that ran into trouble when the symbol was re-emitted
without a name. Removing the name was a giant hack also.

The current version changes the assembly syntax to have an inline
signature spec for TYPEINDEX operands that is always unnamed, which
is much more elegant both in syntax and in implementation (as now the
assembler is able to follow the same path as the regular backend)

Reviewers: sbc100, dschuff, aheejin, jgravelle-google, sunfish, tlively

Subscribers: arphaman, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64758

llvm-svn: 367590

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[WebAssembly] Make LBB markers not affected by test order

Summary:
This way we can change the order of tests or delete some of them without
affecting tests for other functions.

Reviewers: tlively

[WebAssembly] Make LBB markers not affected by test order

Summary:
This way we can change the order of tests or delete some of them without
affecting tests for other functions.

Reviewers: tlively

Subscribers: sunfish, dschuff, sbc100, jgravelle-google, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60929

llvm-svn: 359036

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[WebAssembly] Update CodeGen test expectations after rL354697. NFC

llvm-svn: 354705

[WebAssembly] Fix stack pointer store check in RegStackify

Summary:
We now use __stack_pointer global and global.get/global.set instruction.
This fixes the checking routine for stack_pointer writes

[WebAssembly] Fix stack pointer store check in RegStackify

Summary:
We now use __stack_pointer global and global.get/global.set instruction.
This fixes the checking routine for stack_pointer writes accordingly.

This also fixes the existing __stack_pointer test in reg-stackify.ll:
That test used to pass not because of __stack_pointer clashes but
because the function `stackpointer_callee` was not marked as `readnone`,
so it was assumed to possibly write to memory arbitraily, and
`global.set` instruction was marked as `mayStore` in the .td definition,
so they were identified as intervening writes. After we added `readnone`
to its attribute, this test fails without this patch.

Reviewers: dschuff, sunfish

Subscribers: jgravelle-google, sbc100, llvm-commits

Differential Revision: https://reviews.llvm.org/D56094

llvm-svn: 350906

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[WebAssembly] Massive instruction renaming

Summary:
An automated renaming of all the instructions listed at
https://github.com/WebAssembly/spec/issues/884#issuecomment-426433329
as well as some simi

[WebAssembly] Massive instruction renaming

Summary:
An automated renaming of all the instructions listed at
https://github.com/WebAssembly/spec/issues/884#issuecomment-426433329
as well as some similarly-named identifiers.

Reviewers: aheejin, dschuff, aardappel

Subscribers: sbc100, jgravelle-google, eraman, sunfish, jfb, llvm-commits

Differential Revision: https://reviews.llvm.org/D56338

llvm-svn: 350609

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[WebAssembly] replaced .param/.result by .functype

Summary:
This makes it easier/cleaner to generate a single signature from
this directive. Also:
- Adds the symbol name, such that we don't depend o

[WebAssembly] replaced .param/.result by .functype

Summary:
This makes it easier/cleaner to generate a single signature from
this directive. Also:
- Adds the symbol name, such that we don't depend on the location
of this directive anymore.
- Actually constructs the signature in the assembler, and make the
assembler own it.
- Refactor the use of MVT vs ValType in the streamer and assembler
to require less conversions overall.
- Changed 700 or so tests to use it.

Reviewers: sbc100, dschuff

Subscribers: jgravelle-google, eraman, aheejin, sunfish, jfb, llvm-commits

Differential Revision: https://reviews.llvm.org/D54652

llvm-svn: 347228

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[WebAssembly] Added default stack-only instruction mode for MC.

Summary:
Made it convert from register to stack based instructions, and removed the registers.
Fixes to related code that was expectin

[WebAssembly] Added default stack-only instruction mode for MC.

Summary:
Made it convert from register to stack based instructions, and removed the registers.
Fixes to related code that was expecting register based instructions.
Added the correct testing flag to all tests, depending on what the
format they were expecting so far.
Translated one test to stack format as example: reg-stackify-stack.ll

tested:
llvm-lit -v `find test -name WebAssembly`
unittests/MC/*

Reviewers: dschuff, sunfish

Subscribers: sbc100, jgravelle-google, eraman, aheejin, llvm-commits, jfb

Differential Revision: https://reviews.llvm.org/D51241

llvm-svn: 340750

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Revert "[WebAssembly] Added default stack-only instruction mode for MC."

This reverts commit 917a99b71ce21c975be7bfbf66f4040f965d9f3c.

llvm-svn: 339630

[WebAssembly] Added default stack-only instruction mode for MC.

Summary:
Moved Explicit Locals pass to last.
Made that pass obligatory.
Made it convert from register to stack based instructions, and

[WebAssembly] Added default stack-only instruction mode for MC.

Summary:
Moved Explicit Locals pass to last.
Made that pass obligatory.
Made it convert from register to stack based instructions, and removed the registers.
Fixes to related code that was expecting register based instructions.
Added the correct testing flag to all tests, depending on what the
format they were expecting so far.
Translated one test to stack format as example: reg-stackify-stack.ll

tested:
llvm-lit -v `find test -name WebAssembly`
unittests/MC/*

Reviewers: dschuff, sunfish

Subscribers: jfb, llvm-commits, aheejin, eraman, jgravelle-google, sbc100

Differential Revision: https://reviews.llvm.org/D50568

llvm-svn: 339474

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[WebAssembly] Cleanup of the way globals and global flags are handled

Differential Revision: https://reviews.llvm.org/D44030

llvm-svn: 338894

Revert "[WebAssembly] Added default stack-only instruction mode for MC."

This reverts commit d3c9af4179eae7793d1487d652e2d4e23844555f.
(SVN revision 338164)

llvm-svn: 338176

[WebAssembly] Added default stack-only instruction mode for MC.

Summary:
Moved Explicit Locals pass to last.
Made that pass obligatory.
Made it convert from register to stack based instructions, and

[WebAssembly] Added default stack-only instruction mode for MC.

Summary:
Moved Explicit Locals pass to last.
Made that pass obligatory.
Made it convert from register to stack based instructions, and removed the registers.
Fixes to related code that was expecting register based instructions.
Added the correct testing flag to all tests, depending on what the
format they were expecting so far.
Translated one test to stack format as example: reg-stackify-stack.ll

tested:
llvm-lit -v `find test -name WebAssembly`
unittests/MC/*

Reviewers: dschuff, sunfish

Subscribers: sbc100, jgravelle-google, eraman, aheejin, llvm-commits

Differential Revision: https://reviews.llvm.org/D49160

llvm-svn: 338164

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[WebAsembly] Update default triple in test files to wasm32-unknown-unkown.

Summary: The final -wasm component has been the default for some time now.

Subscribers: jfb, dschuff, jgravelle-google, er

[WebAsembly] Update default triple in test files to wasm32-unknown-unkown.

Summary: The final -wasm component has been the default for some time now.

Subscribers: jfb, dschuff, jgravelle-google, eraman, aheejin, JDevlieghere, sunfish, llvm-commits

Differential Revision: https://reviews.llvm.org/D46342

llvm-svn: 332007

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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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[WebAssembly] Remove infinite loop from reg-stackify test

r310940 exposed reverse-unreachable code to some optimizers,
which caused some of the code in this test to be sunk, changing
the input to th

[WebAssembly] Remove infinite loop from reg-stackify test

r310940 exposed reverse-unreachable code to some optimizers,
which caused some of the code in this test to be sunk, changing
the input to the pass and breaking the exptectations.

Since that change is irrelevant to this particular test, this change
just adds an exit node to work around the problem; the
test should really be more robust (or be an MIR test?) but this preserves
the existing test intent.

llvm-svn: 310981

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[WebAssembly] Use __stack_pointer global when writing wasm binary

This ensures that symbolic relocations are generated for stack
pointer manipulations.

These relocations are of type R_WEBASSEMBLY_G

[WebAssembly] Use __stack_pointer global when writing wasm binary

This ensures that symbolic relocations are generated for stack
pointer manipulations.

These relocations are of type R_WEBASSEMBLY_GLOBAL_INDEX_LEB.
This change also adds support for reading relocations of this
type in WasmObjectFile.cpp.

Since its a globally imported symbol this does mean that
the get_global/set_global instruction won't be valid until
the objects are linked that global used in no longer an
imported global.

Differential Revision: https://reviews.llvm.org/D34172

llvm-svn: 305616

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[WebAssembly] Convert the remaining unit tests to the new wasm-object-file target.

To facilitate this, add a new hidden command-line option to disable
the explicit-locals pass. That causes llc to em

[WebAssembly] Convert the remaining unit tests to the new wasm-object-file target.

To facilitate this, add a new hidden command-line option to disable
the explicit-locals pass. That causes llc to emit invalid code that doesn't
have all locals converted to get_local/set_local, however it simplifies
testwriting in many cases.

llvm-svn: 296540

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[WebAssembly] Fix for 0xc call_indirect changes

Summary:
Need to reorder the operands to have the callee as the last argument.
Adds a pseudo-instruction, and a pass to lower it into a real
call_indi

[WebAssembly] Fix for 0xc call_indirect changes

Summary:
Need to reorder the operands to have the callee as the last argument.
Adds a pseudo-instruction, and a pass to lower it into a real
call_indirect.

This is the first of two options for how to fix the problem.

Reviewers: dschuff, sunfish

Subscribers: jfb, beanz, mgorny, llvm-commits

Differential Revision: https://reviews.llvm.org/D25708

llvm-svn: 284840

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[WebAssemby] Implement block signatures.

Per spec changes, this implements block signatures, and adds just enough
logic to produce correct block signatures at the ends of functions.

Differential Re

[WebAssemby] Implement block signatures.

Per spec changes, this implements block signatures, and adds just enough
logic to produce correct block signatures at the ends of functions.

Differential Revision: https://reviews.llvm.org/D25144

llvm-svn: 283503

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[WebAssembly] Remove the output operand from stores.

Per spec changes, store instructions in WebAssembly no longer have a return
value. Update the instruction descriptions.

Differential Revision: h

[WebAssembly] Remove the output operand from stores.

Per spec changes, store instructions in WebAssembly no longer have a return
value. Update the instruction descriptions.

Differential Revision: https://reviews.llvm.org/D25122

llvm-svn: 283501

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[WebAssembly] Disable the store-results optimization.

The WebAssemly spec removing the return value from store instructions, so
remove the associated optimization from LLVM.

This patch leaves the s

[WebAssembly] Disable the store-results optimization.

The WebAssemly spec removing the return value from store instructions, so
remove the associated optimization from LLVM.

This patch leaves the store instruction operands in place for now, so stores
now always write to "$drop"; these will be removed in a seperate patch.

llvm-svn: 279100

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