[InstCombine] Compute result directly on APInts

If the bitwidth is 2 and we add two 1s, the result may overflow.
This is fine in terms of correctness, but triggers the APInt ctor
assertion. Fix this

[InstCombine] Compute result directly on APInts

If the bitwidth is 2 and we add two 1s, the result may overflow.
This is fine in terms of correctness, but triggers the APInt ctor
assertion. Fix this by performing the calculation directly on APInts.

Fixes the issue reported in:
https://github.com/llvm/llvm-project/pull/114539#issuecomment-2574845003

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[InstCombine] Fold zext(X) + C2 pred C -> X + C3 pred C4 (#110511)

Motivating case from
https://github.com/torvalds/linux/blob/9852d85ec9d492ebef56dc5f229416c925758edc/drivers/gpu/drm/drm_edid.c#L5

[InstCombine] Fold zext(X) + C2 pred C -> X + C3 pred C4 (#110511)

Motivating case from
https://github.com/torvalds/linux/blob/9852d85ec9d492ebef56dc5f229416c925758edc/drivers/gpu/drm/drm_edid.c#L5238-L5240:
```
define i1 @src(i8 noundef %v13) {
entry:
%conv1 = zext i8 %v13 to i32
%add = add nsw i32 %conv1, -4
%cmp = icmp ult i32 %add, 3
%cmp4 = icmp slt i8 %v13, 4
%cond = select i1 %cmp4, i1 true, i1 %cmp
ret i1 %cond
}

define i1 @tgt(i8 noundef %v13) {
entry:
%cmp4 = icmp slt i8 %v13, 7
ret i1 %cmp4
}
```

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[LLVM][IR] Use splat syntax when printing Constant[Data]Vector. (#112548)

[InstCombine] Remove some of the complexity-based canonicalization (#91185)

The idea behind this canonicalization is that it allows us to handle less
patterns, because we know that some will be can

[InstCombine] Remove some of the complexity-based canonicalization (#91185)

The idea behind this canonicalization is that it allows us to handle less
patterns, because we know that some will be canonicalized away. This is
indeed very useful to e.g. know that constants are always on the right.

However, this is only useful if the canonicalization is actually
reliable. This is the case for constants, but not for arguments: Moving
these to the right makes it look like the "more complex" expression is
guaranteed to be on the left, but this is not actually the case in
practice. It fails as soon as you replace the argument with another
instruction.

The end result is that it looks like things correctly work in tests,
while they actually don't. We use the "thwart complexity-based
canonicalization" trick to handle this in tests, but it's often a
challenge for new contributors to get this right, and based on the
regressions this PR originally exposed, we clearly don't get this right
in many cases.

For this reason, I think that it's better to remove this complexity
canonicalization. It will make it much easier to write tests for
commuted cases and make sure that they are handled.

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[InstCombine] Fold an unsigned comparison of `add nsw X, C` with a constant into a signed comparison (#103480)

Given an unsigned integer comparison of `add nsw X, C1` with some
constant `C2` we can

[InstCombine] Fold an unsigned comparison of `add nsw X, C` with a constant into a signed comparison (#103480)

Given an unsigned integer comparison of `add nsw X, C1` with some
constant `C2` we can fold it into a signed comparison of `X` and `C2 -
C1` under the following conditions:
* There's a `nsw` flag on the addition
* `C2` is non-negative
* `X + C1` is non-negative
* `C2 - C1` is non-negative

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[InstCombine] Canonicalize `icmp ult (add X, C2), C` expressions

`icmp ult (add X, C2), C` can be folded to `icmp ne (and X, C), 2C`,
subject to `C == -C2` and C2 being a power of 2.

Proofs: https:

[InstCombine] Canonicalize `icmp ult (add X, C2), C` expressions

`icmp ult (add X, C2), C` can be folded to `icmp ne (and X, C), 2C`,
subject to `C == -C2` and C2 being a power of 2.

Proofs: https://alive2.llvm.org/ce/z/P-VVmQ.

Fixes: https://github.com/llvm/llvm-project/issues/75613.

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[InstCombine] Fold `(icmp eq/ne (add nuw x, y), 0)` -> `(icmp eq/ne (or x, y), 0)`

`(icmp eq/ne (or x, y), 0)` is probably easier to analyze than `(icmp
eq/ne x, -y)`

Proof: https://alive2.llvm.org

[InstCombine] Fold `(icmp eq/ne (add nuw x, y), 0)` -> `(icmp eq/ne (or x, y), 0)`

`(icmp eq/ne (or x, y), 0)` is probably easier to analyze than `(icmp
eq/ne x, -y)`

Proof: https://alive2.llvm.org/ce/z/2-VTb6

Closes #88088

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[InstCombine] Add tests for folding `(icmp eq/ne (add nuw x, y), 0)`; NFC

[InstCombine] Extend `sext`/`zext` boolean additions to vectors

Reported-by: shao-hua-li

Fixes: https://github.com/llvm/llvm-project/issues/68745.

[InstCombine] Fold comparison of adding two z/sext booleans (#67895)

- Add test coverage for sext/zext boolean additions
- [InstCombine] Fold comparison of adding two z/sext booleans

Fixes https

[InstCombine] Fold comparison of adding two z/sext booleans (#67895)

- Add test coverage for sext/zext boolean additions
- [InstCombine] Fold comparison of adding two z/sext booleans

Fixes https://github.com/llvm/llvm-project/issues/64859.

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[InstCombine] Add test coverage for sext/zext boolean additions (NFC)

Tests for #67895.

[InstCombine] Regenerate all test checks (NFC)

Due to an improvement to name preservation, a lot of InstCombine
tests now show spurious diffs when regenerated.

Rather than regenerating individual f

[InstCombine] Regenerate all test checks (NFC)

Due to an improvement to name preservation, a lot of InstCombine
tests now show spurious diffs when regenerated.

Rather than regenerating individual files when they get touched,
mass-regenerate all UTC-based InstCombine tests. I have then reset
a number of files showing suspicious diffs where the UTC output
has clearly been manually adjusted. I apologize if I missed
anything in the mass of changes.

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[test][InstCombine] Update some test cases to use opaque pointers

These tests cases were converted using the script at
https://gist.github.com/nikic/98357b71fd67756b0f064c9517b62a34

Differential Re

[test][InstCombine] Update some test cases to use opaque pointers

These tests cases were converted using the script at
https://gist.github.com/nikic/98357b71fd67756b0f064c9517b62a34

Differential Revision: https://reviews.llvm.org/D135094

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[InstCombine] Fold ult(add(x,-1),c) -> ule(x,c) iff x != 0 (PR57635)

Alive2: https://alive2.llvm.org/ce/z/sZ6wwS

As detailed on Issue #57635 and #37628 - for unsigned comparisons, we can compare pr

[InstCombine] Fold ult(add(x,-1),c) -> ule(x,c) iff x != 0 (PR57635)

Alive2: https://alive2.llvm.org/ce/z/sZ6wwS

As detailed on Issue #57635 and #37628 - for unsigned comparisons, we can compare prior to a decrement iff the value is known never to be zero.

Differential Revision: https://reviews.llvm.org/D134172

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[InstCombine] Add test coverage for D134172 / Issue #57635

[InstCombine] Fold X + Y + C u< X

This is a variation on the X + Y u< X fold with an extra constant.
Proof: https://alive2.llvm.org/ce/z/VNb8pY

[InstCombine] Add additional tests for X + Y + C u< X (NFC)

We don't actually need the limitation for C == -1, so update test
naming accordingly, and also test a non-uniform vector constant.

[InstCombine] Add tests for X + Y - 1 u< X (NFC)

[InstCombine] Canonicalize SPF to min/max intrinsics

Now that integer min/max intrinsics have good support in both
InstCombine and other passes, start canonicalizing SPF min/max
to intrinsic min/max

[InstCombine] Canonicalize SPF to min/max intrinsics

Now that integer min/max intrinsics have good support in both
InstCombine and other passes, start canonicalizing SPF min/max
to intrinsic min/max.

Once this sticks, we can stop matching SPF min/max in various
places, and can remove hacks we have for preventing infinite loops
and breaking of SPF canonicalization.

Differential Revision: https://reviews.llvm.org/D98152

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[test] Use -passes=instcombine instead of -instcombine in lots of tests. NFC

Another step moving away from the deprecated syntax of specifying
pass pipeline in opt.

Differential Revision: https://r

[test] Use -passes=instcombine instead of -instcombine in lots of tests. NFC

Another step moving away from the deprecated syntax of specifying
pass pipeline in opt.

Differential Revision: https://reviews.llvm.org/D119081

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[InstCombine] Canonicalize range test idiom

InstCombine converts range tests of the form (X > C1 && X < C2) or
(X < C1 || X > C2) into checks of the form (X + C3 < C4) or
(X + C3 > C4). It is possib

[InstCombine] Canonicalize range test idiom

InstCombine converts range tests of the form (X > C1 && X < C2) or
(X < C1 || X > C2) into checks of the form (X + C3 < C4) or
(X + C3 > C4). It is possible to express all range tests in either
of these forms (with different choices of constants), but currently
neither of them is considered canonical. We may have equivalent
range tests using either ult or ugt.

This proposes to canonicalize all range tests to use ult. An
alternative would be to canonicalize to either ult or ugt depending
on the specific constants involved -- e.g. in practice we currently
generate ult for && style ranges and ugt for || style ranges when
going through the insertRangeTest() helper. In fact, the "clamp like"
fold was relying on this, which is why I had to tweak it to not
assume whether inversion is needed based on just the predicate.

Proof: https://alive2.llvm.org/ce/z/_SP_rQ

Differential Revision: https://reviews.llvm.org/D113366

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[InstCombine] avoid breaking up min/max (cmp+sel) idioms

This is a quick fix for a motivating case that looks like this:
https://godbolt.org/z/GeMqzMc38

As noted, we might be able to restore the mi

[InstCombine] avoid breaking up min/max (cmp+sel) idioms

This is a quick fix for a motivating case that looks like this:
https://godbolt.org/z/GeMqzMc38

As noted, we might be able to restore the min/max patterns
with select folds, or we just wait for this to become easier
with canonicalization to min/max intrinsics.

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[InstCombine] add tests for inc/dec with min/max; NFC

[InstCombine] reorder icmp with offset folds for better results

This set of folds was added recently with:
c7b658aeb526
0c400e895306
40b752d28d95

...and I noted that this wasn't likely to fire in c

[InstCombine] reorder icmp with offset folds for better results

This set of folds was added recently with:
c7b658aeb526
0c400e895306
40b752d28d95

...and I noted that this wasn't likely to fire in code derived
from C/C++ source because of nsw in particular. But I didn't
notice that I had placed the code above the no-wrap block
of transforms.

This is likely the cause of regressions noted from the previous
commit because -- as shown in the test diffs -- we may have
transformed into a compare with an arbitrary constant rather
than a simpler signbit test.

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[InstCombine] add tests for icmp with constant offset and no-wrap flags; NFC