[InstSimplify] Convert tests to opaque pointers (NFC)

The only interesting test change is in @PR31262, where the following
fold is now performed, while it previously was not:
https://alive2.llvm.org

[InstSimplify] Convert tests to opaque pointers (NFC)

The only interesting test change is in @PR31262, where the following
fold is now performed, while it previously was not:
https://alive2.llvm.org/ce/z/a5Qmr6

llvm/test/Transforms/InstSimplify/ConstProp/gep.ll has not been
updated, because there is a tradeoff between folding and inrange
preservation there that we may want to discuss.

Updates have been performed using:
https://gist.github.com/nikic/98357b71fd67756b0f064c9517b62a34

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[test] Use -passes=instsimplify instead of -instsimplify in a number of tests. NFC

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

Differential Revision: htt

[test] Use -passes=instsimplify instead of -instsimplify in a number of tests. NFC

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

Differential Revision: https://reviews.llvm.org/D119080

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[InstSimplify] Pass SimplifyQuery into simplifyUnsignedRangeCheck() and use it for isKnownNonZero()

This was actually the original intention in D67332,
but i messed up and forgot about it.
This patc

[InstSimplify] Pass SimplifyQuery into simplifyUnsignedRangeCheck() and use it for isKnownNonZero()

This was actually the original intention in D67332,
but i messed up and forgot about it.
This patch was originally part of D67411, but precommitting this.

llvm-svn: 371630

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[NFC][InstSimplify] Add extra test for D67411 with @llvm.assume

llvm-svn: 371629

[InstSimplify] simplifyUnsignedRangeCheck(): if we know that X != 0, handle more cases (PR43246)

Summary:
This is motivated by D67122 sanitizer check enhancement.
That patch seemingly worsens `-fsan

[InstSimplify] simplifyUnsignedRangeCheck(): if we know that X != 0, handle more cases (PR43246)

Summary:
This is motivated by D67122 sanitizer check enhancement.
That patch seemingly worsens `-fsanitize=pointer-overflow`
overhead from 25% to 50%, which strongly implies missing folds.

In this particular case, given
```
char* test(char& base, unsigned long offset) {
return &base + offset;
}
```
it will end up producing something like
https://godbolt.org/z/LK5-iH
which after optimizations reduces down to roughly
```
define i1 @t0(i8* nonnull %base, i64 %offset) {
%base_int = ptrtoint i8* %base to i64
%adjusted = add i64 %base_int, %offset
%non_null_after_adjustment = icmp ne i64 %adjusted, 0
%no_overflow_during_adjustment = icmp uge i64 %adjusted, %base_int
%res = and i1 %non_null_after_adjustment, %no_overflow_during_adjustment
ret i1 %res
}
```
Without D67122 there was no `%non_null_after_adjustment`,
and in this particular case we can get rid of the overhead:

Here we add some offset to a non-null pointer,
and check that the result does not overflow and is not a null pointer.
But since the base pointer is already non-null, and we check for overflow,
that overflow check will already catch the null pointer,
so the separate null check is redundant and can be dropped.

Alive proofs:
https://rise4fun.com/Alive/WRzq

There are more patterns of "unsigned-add-with-overflow", they are not handled here,
but this is the main pattern, that we currently consider canonical,
so it makes sense to handle it.

https://bugs.llvm.org/show_bug.cgi?id=43246

Reviewers: spatel, nikic, vsk

Reviewed By: spatel

Subscribers: hiraditya, llvm-commits, reames

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67332

llvm-svn: 371349

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[NFC][InstSimplify] Some tests for dropping null check after uadd.with.overflow of non-null (PR43246)

https://rise4fun.com/Alive/WRzq

Name: C <= Y && Y != 0 --> C <= Y iff C != 0
Pre: C != 0
%

[NFC][InstSimplify] Some tests for dropping null check after uadd.with.overflow of non-null (PR43246)

https://rise4fun.com/Alive/WRzq

Name: C <= Y && Y != 0 --> C <= Y iff C != 0
Pre: C != 0
%y_is_nonnull = icmp ne i64 %y, 0
%no_overflow = icmp ule i64 C, %y
%r = and i1 %y_is_nonnull, %no_overflow
=>
%r = %no_overflow

Name: C <= Y || Y != 0 --> Y != 0 iff C != 0
Pre: C != 0
%y_is_nonnull = icmp ne i64 %y, 0
%no_overflow = icmp ule i64 C, %y
%r = or i1 %y_is_nonnull, %no_overflow
=>
%r = %y_is_nonnull

Name: C > Y || Y == 0 --> C > Y iff C != 0
Pre: C != 0
%y_is_null = icmp eq i64 %y, 0
%overflow = icmp ugt i64 C, %y
%r = or i1 %y_is_null, %overflow
=>
%r = %overflow

Name: C > Y && Y == 0 --> Y == 0 iff C != 0
Pre: C != 0
%y_is_null = icmp eq i64 %y, 0
%overflow = icmp ugt i64 C, %y
%r = and i1 %y_is_null, %overflow
=>
%r = %y_is_null

https://bugs.llvm.org/show_bug.cgi?id=43246

llvm-svn: 371339

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