[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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[Reland][InstCombine] Fold `icmp eq/ne min|max(X, Y), Z` (#67087)

This patch further improves the simplification of pattern `icmp eq/ne
min|max(X, Y), Z` as discussed in
[D156238](https://reviews.ll

[Reland][InstCombine] Fold `icmp eq/ne min|max(X, Y), Z` (#67087)

This patch further improves the simplification of pattern `icmp eq/ne
min|max(X, Y), Z` as discussed in
[D156238](https://reviews.llvm.org/D156238).
When `X < Z`:
`min(X, Y) == Z -> false`
`min(X, Y) != Z -> true`
`max(X, Y) == Z -> Y == Z`
`max(Y, Z) != Z -> Y != Z`
When `X > Z`:
`max(X, Y) == Z -> false`
`max(X, Y) != Z -> true`
`min(X, Y) == Z -> Y == Z`
`min(Y, Z) != Z -> Y != Z`

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

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Revert "[InstCombine] Fold `icmp eq/ne min|max(X, Y), Z` (#67087)"

Details in https://reviews.llvm.org/D156238

This reverts commit d2abe8dc662a94e6c9aca5b64af53c7f815b5701.

[InstCombine] Fold `icmp eq/ne min|max(X, Y), Z` (#67087)

This patch further improves the simplification of pattern `icmp eq/ne
min|max(X, Y), Z` as discussed in
[D156238](https://reviews.llvm.org

[InstCombine] Fold `icmp eq/ne min|max(X, Y), Z` (#67087)

This patch further improves the simplification of pattern `icmp eq/ne
min|max(X, Y), Z` as discussed in
[D156238](https://reviews.llvm.org/D156238).
When `X < Z`:
`min(X, Y) == Z -> false`
`min(X, Y) != Z -> true`
`max(X, Y) == Z -> Y == Z`
`max(Y, Z) != Z -> Y != Z`
When `X > Z`:
`max(X, Y) == Z -> false`
`max(X, Y) != Z -> true`
`min(X, Y) == Z -> Y == Z`
`min(Y, Z) != Z -> Y != Z`

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

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[InstCombine] Generalize foldICmpWithMinMax

This patch generalizes the fold of `icmp pred min/max(X, Y), Z` to address the issue https://github.com/llvm/llvm-project/issues/62898.

For example, we c

[InstCombine] Generalize foldICmpWithMinMax

This patch generalizes the fold of `icmp pred min/max(X, Y), Z` to address the issue https://github.com/llvm/llvm-project/issues/62898.

For example, we can fold `smin(X, Y) < Z` into `X < Z` when `Y > Z` is implied by constant folds/invariants/dom conditions.

Alive2 (with `--disable-undef-input` due to the limitation of --smt-to=10000): https://alive2.llvm.org/ce/z/rB7qLc
You can run the standalone translation validation tool `alive-tv` locally to verify these transformations.
```
alive-tv transforms.ll --smt-to=600000 --exit-on-error
```

Reviewed By: goldstein.w.n

Differential Revision: https://reviews.llvm.org/D156238

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[InstCombine] Add test cases from PR62898. NFC.

This patch adds some test cases from https://github.com/llvm/llvm-project/issues/62898.

As nikic noted in the issue, we should start by implementing

[InstCombine] Add test cases from PR62898. NFC.

This patch adds some test cases from https://github.com/llvm/llvm-project/issues/62898.

As nikic noted in the issue, we should start by implementing a generalization of the fold `smin(X, Y) < Z -> X < Z` when `Y > Z` is implied by constant folds/invariants/dom conditions.
```
define i1 @src(i32 %x, i32 %y, i32 %z) {
%cmp = icmp sgt i32 %y, %z
br i1 %cmp, label %if, label %end
if:
%cond = call i32 @llvm.smin.i32(i32 %x, i32 %y)
%tobool = icmp slt i32 %cond, %z
ret i1 %tobool
end:
ret i1 false
}

define i1 @tgt(i32 %x, i32 %y, i32 %z) {
%cmp = icmp sgt i32 %y, %z
br i1 %cmp, label %if, label %end
if:
%tobool = icmp slt i32 %x, %z
ret i1 %tobool
end:
ret i1 false
}

declare i32 @llvm.smin.i32(i32, i32)
```
Alive2: https://alive2.llvm.org/ce/z/dK9vXz

This patch also adds some generalized test cases like the above.

Reviewed By: goldstein.w.n

Differential Revision: https://reviews.llvm.org/D156227

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[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] Regenerate test checks (NFC)

Revert "Temporarily Revert "Add basic loop fusion pass.""

The reversion apparently deleted the test/Transforms directory.

Will be re-reverting again.

llvm-svn: 358552

[InstCombine] add folds for icmp (smin X, Y), X

Min/max canonicalization (r287585) exposes the fact that we're missing combines for min/max patterns.
This patch won't solve the example that was att

[InstCombine] add folds for icmp (smin X, Y), X

Min/max canonicalization (r287585) exposes the fact that we're missing combines for min/max patterns.
This patch won't solve the example that was attached to that thread, so something else still needs fixing.

The line between InstCombine and InstSimplify gets blurry here because sometimes the icmp instruction that
we want to fold to already exists, but sometimes it's the swapped form of what we want.

Corresponding changes for smax/umin/umax to follow.

Differential Revision: https://reviews.llvm.org/D27531

llvm-svn: 289855

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[InstCombine] add tests for smin+icmp; NFC

The tests that already work are folded in InstSimplify, so those
tests should be redundant and we can remove them if they don't
seem worthwhile for complet

[InstCombine] add tests for smin+icmp; NFC

The tests that already work are folded in InstSimplify, so those
tests should be redundant and we can remove them if they don't
seem worthwhile for completeness.

llvm-svn: 288957

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