GlobalISel: Implement computeKnownBits for overflow bool results

Reapply "Revert "GlobalISel: Add G_ASSERT_ALIGN hint instruction"

This reverts commit a97e20a3a8a58be751f023e610758310d5664562.

Revert "GlobalISel: Add G_ASSERT_ALIGN hint instruction"

This commit sometimes causes a crash when compiling a vtable thunk. E.g.:

clang '--target=aarch64-grtev4-linux-gnu' -xc++ - -c -o /dev/null

Revert "GlobalISel: Add G_ASSERT_ALIGN hint instruction"

This commit sometimes causes a crash when compiling a vtable thunk. E.g.:

clang '--target=aarch64-grtev4-linux-gnu' -xc++ - -c -o /dev/null <<EOF
struct a {
virtual int f();
};
struct c {
virtual int &g() const;
};
struct d : a, c {
int &g() const;
};
int &d::g() const {}
EOF

Some follow-up commits have been reverted as well:
Revert "IR: Make getRetAlign check callee function attributes"
Revert "Fix MSVC "32-bit shift implicitly converted to 64 bits" warning. NFC."
Revert "Fix MSVC "32-bit shift implicitly converted to 64 bits" warning. NFC."

This reverts commit 4f414af6a77cdbd9b6303a7afa525cfb3f9d792a.
This reverts commit a5507d2e253a2c94c3ca7794edf7385af8082b97.
This reverts commit 3d2d208f6a0a421b23937c39b9d371183a5913a3.
This reverts commit 07ddfa95e3b5ea8464e90545f592624221b854ae.

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Fix MSVC "32-bit shift implicitly converted to 64 bits" warning. NFC.

GlobalISel: Add G_ASSERT_ALIGN hint instruction

Insert it for call return values only for now, which is the only case
the DAG handles also.

[APInt] Normalize naming on keep constructors / predicate methods.

This renames the primary methods for creating a zero value to `getZero`
instead of `getNullValue` and renames predicates like `isAl

[APInt] Normalize naming on keep constructors / predicate methods.

This renames the primary methods for creating a zero value to `getZero`
instead of `getNullValue` and renames predicates like `isAllOnesValue`
to simply `isAllOnes`. This achieves two things:

1) This starts standardizing predicates across the LLVM codebase,
following (in this case) ConstantInt. The word "Value" doesn't
convey anything of merit, and is missing in some of the other things.

2) Calling an integer "null" doesn't make any sense. The original sin
here is mine and I've regretted it for years. This moves us to calling
it "zero" instead, which is correct!

APInt is widely used and I don't think anyone is keen to take massive source
breakage on anything so core, at least not all in one go. As such, this
doesn't actually delete any entrypoints, it "soft deprecates" them with a
comment.

Included in this patch are changes to a bunch of the codebase, but there are
more. We should normalize SelectionDAG and other APIs as well, which would
make the API change more mechanical.

Differential Revision: https://reviews.llvm.org/D109483

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[GlobalISel][KnownBits] Implement G_CTPOP

Implementation copied almost verbatim from ValueTracking.

Differential revision: https://reviews.llvm.org/D107606

Revert "[GlobalISel][KnownBits] Implement G_CTPOP"

This reverts commit ce6eb4f15a159e652bdccf92a9d3da8a972d1596.

It's broken on the windows bots: https://reviews.llvm.org/D107606#2930121

[GlobalISel][KnownBits] Implement G_CTPOP

Implementation copied almost verbatim from ValueTracking.

Differential revision: https://reviews.llvm.org/D107606

[GlobalISel] Fix known bits for G_BSWAP and B_BITREVERSE not doing anything.

llvm::KnownBits::byteSwap() and reverse() don't modify in-place, so
we weren't actually computing anything. This was caus

[GlobalISel] Fix known bits for G_BSWAP and B_BITREVERSE not doing anything.

llvm::KnownBits::byteSwap() and reverse() don't modify in-place, so
we weren't actually computing anything. This was causing a miscompile on an
arm64 stage2 bootstrap clang build.

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CodeGen: Print/parse LLTs in MachineMemOperands

This will currently accept the old number of bytes syntax, and convert
it to a scalar. This should be removed in the near future (I think I
converted

CodeGen: Print/parse LLTs in MachineMemOperands

This will currently accept the old number of bytes syntax, and convert
it to a scalar. This should be removed in the near future (I think I
converted all of the tests already, but likely missed a few).

Not sure what the exact syntax and policy should be. We can continue
printing the number of bytes for non-generic instructions to avoid
test churn and only allow non-scalar types for generic instructions.

This will currently print the LLT in parentheses, but accept parsing
the existing integers and implicitly converting to scalar. The
parentheses are a bit ugly, but the parser logic seems unable to deal
without either parentheses or some keyword to indicate the start of a
type.

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[GlobalISel] Add G_SBFX/G_UBFX to computeKnownBits

Differential Revision: https://reviews.llvm.org/D102969

Revert "[globalisel][unittests] Rename setUp() to avoid potential mix up with SetUp() from gtest"

Forgot to apply commit message changes from phabricator

This reverts commit 3a016e31ecef7eeb876b540

Revert "[globalisel][unittests] Rename setUp() to avoid potential mix up with SetUp() from gtest"

Forgot to apply commit message changes from phabricator

This reverts commit 3a016e31ecef7eeb876b540c928a25a7c5d2e07a.

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[globalisel][unittests] Rename setUp() to avoid potential mix up with SetUp() from gtest

Also, make it structurally required so it can't be forgotten and re-introduce
the bug that led to the rotten

[globalisel][unittests] Rename setUp() to avoid potential mix up with SetUp() from gtest

Also, make it structurally required so it can't be forgotten and re-introduce
the bug that led to the rotten green tests.

Differential Revision: https://reviews.llvm.org/D99692

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Reland [GlobalISel] Start using vectors in GISelKnownBits

This is recommit of 4c8fb7ddd6fa49258e0e9427e7345fb56ba522d4.
MIR in one unit test had mismatched types.

For vectors we consider a bit as k

Reland [GlobalISel] Start using vectors in GISelKnownBits

This is recommit of 4c8fb7ddd6fa49258e0e9427e7345fb56ba522d4.
MIR in one unit test had mismatched types.

For vectors we consider a bit as known if it is the same for all demanded
vector elements (all elements by default). KnownBits BitWidth for vector
type is size of vector element. Add support for G_BUILD_VECTOR.
This allows combines of urem_pow2_to_mask in pre-legalizer combiner.

Differential Revision: https://reviews.llvm.org/D96122

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Revert "[GlobalISel] Start using vectors in GISelKnownBits"

This reverts commit 4c8fb7ddd6fa49258e0e9427e7345fb56ba522d4.
Breaks check-llvm everywhere, see https://reviews.llvm.org/D96122

[GlobalISel] Start using vectors in GISelKnownBits

For vectors we consider a bit as known if it is the same for all demanded
vector elements (all elements by default). KnownBits BitWidth for vector

[GlobalISel] Start using vectors in GISelKnownBits

For vectors we consider a bit as known if it is the same for all demanded
vector elements (all elements by default). KnownBits BitWidth for vector
type is size of vector element. Add support for G_BUILD_VECTOR.
This allows combines of urem_pow2_to_mask in pre-legalizer combiner.

Differential Revision: https://reviews.llvm.org/D96122

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[GlobalISel] Implement computeKnownBits for G_ASSERT_SEXT

Implementation is the same as G_SEXT_INREG.

Differential Revision: https://reviews.llvm.org/D96899

[GlobalISel] Implement computeNumSignBits for G_ASSERT_SEXT

Same implementation as G_SEXT_INREG.

Add a testcase to combine-sext-inreg for a concrete example, and a testcase
to KnownBitsTest.

Diffe

[GlobalISel] Implement computeNumSignBits for G_ASSERT_SEXT

Same implementation as G_SEXT_INREG.

Add a testcase to combine-sext-inreg for a concrete example, and a testcase
to KnownBitsTest.

Differential Revision: https://reviews.llvm.org/D96897

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[GlobalISel] Implement computeKnownBits for G_ASSERT_ZEXT

It's the same as the ZEXT/TRUNC case, except SrcBitWidth is given by the
immediate operand.

Update KnownBitsTest.cpp and a MIR test for a c

[GlobalISel] Implement computeKnownBits for G_ASSERT_ZEXT

It's the same as the ZEXT/TRUNC case, except SrcBitWidth is given by the
immediate operand.

Update KnownBitsTest.cpp and a MIR test for a concrete example.

Differential Revision: https://reviews.llvm.org/D95566

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[GlobalISel] Implement computeKnownBits for G_SEXT_INREG

Just use the existing `Known.sextInReg` implementation.

- Update KnownBitsTest.cpp.
- Update combine-redundant-and.mir for a more concrete e

[GlobalISel] Implement computeKnownBits for G_SEXT_INREG

Just use the existing `Known.sextInReg` implementation.

- Update KnownBitsTest.cpp.
- Update combine-redundant-and.mir for a more concrete example.

Differential Revision: https://reviews.llvm.org/D95484

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GlobalISel: Add isKnownToBeAPowerOfTwo helper function

Revert rGbbeb08497ce58 "Revert "[GlobalISel] GISelKnownBits::computeKnownBitsImpl - Replace TargetOpcode::G_MUL handling with the common KnownBits::computeForMul implementation""

Updated the GISel K

Revert rGbbeb08497ce58 "Revert "[GlobalISel] GISelKnownBits::computeKnownBitsImpl - Replace TargetOpcode::G_MUL handling with the common KnownBits::computeForMul implementation""

Updated the GISel KnownBits tests as KnownBits::computeForMul allows more accurate computation.

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[GlobalISel][KnownBits] Early return on out of bound shift amounts

If the known shift amount is bigger than or equal to the bitwidth of the type of the value to be shifted,
the result is target depe

[GlobalISel][KnownBits] Early return on out of bound shift amounts

If the known shift amount is bigger than or equal to the bitwidth of the type of the value to be shifted,
the result is target dependent, so don't try to infer any bits.

This fixes a crash we've seen in one of our internal test suites.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D89232

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[KnownBits] Implement accurate unsigned and signed max and min

Use the new implementation in ValueTracking, SelectionDAG and
GlobalISel.

Differential Revision: https://reviews.llvm.org/D87034