[SCEV] Extend type hint in analysis output to all backedge kinds

This extends the work from 7755c26 to all of the different backend
taken count kinds that we print for the scev analysis printer. As

[SCEV] Extend type hint in analysis output to all backedge kinds

This extends the work from 7755c26 to all of the different backend
taken count kinds that we print for the scev analysis printer. As
before, the goal is to cut down on confusion as i4 -1 is a very
different (unsigned) value from i32 -1.

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[SCEV] Print predicate backedge count only if new information available

When printing the result of SCEV's analysis, we can avoid printing
the predicated backedge taken count and the predicates if t

[SCEV] Print predicate backedge count only if new information available

When printing the result of SCEV's analysis, we can avoid printing
the predicated backedge taken count and the predicates if the predicates
are empty and no new information is provided. This helps to reduce the
verbosity of the output.

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[SCEV] Include type when printing constant max backedge taken count

When printing the result of the analysis, i8 -1 and i64 -1 are quite
different in terms of analysis quality. In a recent conversi

[SCEV] Include type when printing constant max backedge taken count

When printing the result of the analysis, i8 -1 and i64 -1 are quite
different in terms of analysis quality. In a recent conversion with
a new contributor, we ran into exactly this confusion.

Adding the type for constant scevs more globally seems worthwhile, but
introduces a much larger test diff. I'm splitting this off first since
it addresses the immediate need, and then going to do some further
changes to clarify a few related bits of analysis result output.

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[SCEV] Migrate some tests to be autogenerated

In advance of a change which needs to update these. This batch was the
"easy" ones, I'll be landing the harder set a few a time for easier
review.

[SCEV] Convert some tests to opaque pointers (NFC)

[SCEV] Rename max backedge-taken count -> constant max backedge taken-count in printout

This is a preparatory step for introducing symbolic max backedge-taken count.

[test][NewPM] Remove RUN lines using -analyze

Only tests in llvm/test/Analysis.

-analyze is legacy PM-specific.

This only touches files with `-passes`.

I looked through everything and made sure t

[test][NewPM] Remove RUN lines using -analyze

Only tests in llvm/test/Analysis.

-analyze is legacy PM-specific.

This only touches files with `-passes`.

I looked through everything and made sure that everything had a new PM equivalent.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D109040

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[SCEV] Fix ScalarEvolution tests under NPM

Many tests use opt's -analyze feature, which does not translate well to
NPM and has better alternatives. The alternative here is to explicitly
add a pass t

[SCEV] Fix ScalarEvolution tests under NPM

Many tests use opt's -analyze feature, which does not translate well to
NPM and has better alternatives. The alternative here is to explicitly
add a pass that calls ScalarEvolution::print().

The legacy pass manager RUNs aren't changing, but they are now pinned to
the legacy pass manager. For each legacy pass manager RUN, I added a
corresponding NPM RUN using the 'print<scalar-evolution>' pass. For
compatibility with update_analyze_test_checks.py and existing test
CHECKs, 'print<scalar-evolution>' now prints what -analyze prints per
function.

This was generated by the following Python script and failures were
manually fixed up:

import sys
for i in sys.argv:
with open(i, 'r') as f:
s = f.read()
with open(i, 'w') as f:
for l in s.splitlines():
if "RUN:" in l and ' -analyze ' in l and '\\' not in l:
f.write(l.replace(' -analyze ', ' -analyze -enable-new-pm=0 '))
f.write('\n')
f.write(l.replace(' -analyze ', ' -disable-output ').replace(' -scalar-evolution ', ' "-passes=print<scalar-evolution>" ').replace(" | ", " 2>&1 | "))
f.write('\n')
else:
f.write(l)

There are a couple failures still in ScalarEvolution under NPM, but
those are due to other unrelated naming conflicts.

Reviewed By: asbirlea

Differential Revision: https://reviews.llvm.org/D83798

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[SCEV] Fix predicate usage in computeExitLimitFromICmp

In this method, we invoke `SimplifyICmpOperands` which takes the `Cond` predicate
by reference and may change it along with `LHS` and `RHS` SCE

[SCEV] Fix predicate usage in computeExitLimitFromICmp

In this method, we invoke `SimplifyICmpOperands` which takes the `Cond` predicate
by reference and may change it along with `LHS` and `RHS` SCEVs. But then we invoke
`computeShiftCompareExitLimit` with Values from which the SCEVs have been derived,
these Values have not been modified while `Cond` could be.

One of possible outcomes of this is that we may falsely prove that an infinite loop ends
within some finite number of iterations.

In this patch, we save the original `Cond` and pass it along with original operands.
This logic may be removed in future once `computeShiftCompareExitLimit` works
with SCEVs instead of value operands.

Reviewed By: sanjoy
Differential Revision: https://reviews.llvm.org/D40953

llvm-svn: 320142

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[SCEV] Compute max backedge count for loops with "shift ivs"

This teaches SCEV to compute //max// backedge taken counts for loops
like

for (int i = k; i != 0; i >>>= 1)
whatever();

SCEV

[SCEV] Compute max backedge count for loops with "shift ivs"

This teaches SCEV to compute //max// backedge taken counts for loops
like

for (int i = k; i != 0; i >>>= 1)
whatever();

SCEV yet cannot represent the exact backedge count for these loops, and
this patch does not change that. This is really geared towards teaching
SCEV that loops like the above are *not* infinite.

llvm-svn: 251558

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