[Bug tree-optimization/114121] wrong code with _BitInt() arithmetics at -O2

["rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114121

--- Comment #9 from Richard Biener <rguenth at gcc dot gnu.org> ---
Which of course would regress something like

int a[16];
int foo (int i)
{
  if (i > 7)
    return a[i];
  else
    return a[i];
}

where we'd no longer hoist as we no longer would value-number the refs the
same (that extends to any ref using SSA names with eventually differing
ranges).  Reverting r9-398 likely isn't the best answer either, it would
of course also regress the two valid replacements with zero (the prototype
patch preserves those).

There's the PR100923 fix (r12-1295-g7a56d3d3e99cc7) which targeted a similar
(but even more odd) case with "contextual" PTA info (though there's really no
such thing).
But it didn't really fix the contextual thing but added re-valueization
which in case of vn_reference_lookup_pieces works on value-numbered refs
where failure mode is keeping the value-number.

The prototype (after fixing it a bit) passes bootstrap but regresses quite
some number of testcases (maybe due to ???s present).

FAIL: g++.dg/ipa/devirt-20.C  -std=gnu++98  scan-tree-dump-not release_ssa
"abor
t"
FAIL: g++.dg/ipa/devirt-20.C  -std=gnu++14  scan-tree-dump-not release_ssa
"abor
t"
FAIL: g++.dg/ipa/devirt-20.C  -std=gnu++17  scan-tree-dump-not release_ssa
"abor
t"
FAIL: g++.dg/ipa/devirt-20.C  -std=gnu++20  scan-tree-dump-not release_ssa
"abort"
FAIL: g++.dg/opt/pr110879.C  -std=gnu++14  scan-tree-dump-not optimized
"=\\\\s*\\\\S*res_(?!\\\\S*_M_end_of_storage;)"
FAIL: g++.dg/opt/pr110879.C  -std=gnu++17  scan-tree-dump-not optimized
"=\\\\s*\\\\S*res_(?!\\\\S*_M_end_of_storage;)"
FAIL: g++.dg/opt/pr110879.C  -std=gnu++20  scan-tree-dump-not optimized
"=\\\\s*\\\\S*res_(?!\\\\S*_M_end_of_storage;)"
FAIL: g++.dg/pr99966.C  -std=gnu++17  scan-tree-dump-not vrp1 "throw"
FAIL: g++.dg/pr99966.C  -std=gnu++20  scan-tree-dump-not vrp1 "throw"
FAIL: g++.dg/vect/pr112961.cc  -std=c++98  scan-tree-dump vect "LOOP
VECTORIZED"
FAIL: g++.dg/vect/pr112961.cc  -std=c++14  scan-tree-dump vect "LOOP
VECTORIZED"
FAIL: g++.dg/vect/pr112961.cc  -std=c++17  scan-tree-dump vect "LOOP
VECTORIZED"
FAIL: g++.dg/vect/pr112961.cc  -std=c++20  scan-tree-dump vect "LOOP
VECTORIZED"
FAIL: g++.dg/vect/pr89653.cc  -std=c++98  scan-tree-dump vect "vectorized 1
loops"
FAIL: g++.dg/vect/pr89653.cc  -std=c++14  scan-tree-dump vect "vectorized 1
loops"
FAIL: g++.dg/vect/pr89653.cc  -std=c++17  scan-tree-dump vect "vectorized 1
loops"
FAIL: g++.dg/vect/pr89653.cc  -std=c++20  scan-tree-dump vect "vectorized 1
loops"
FAIL: g++.dg/vect/simd-10.cc  -std=c++98  scan-tree-dump-times vect "vectorized
[1-3] loops" 2
FAIL: g++.dg/vect/simd-10.cc  -std=c++14  scan-tree-dump-times vect "vectorized
[1-3] loops" 2
FAIL: g++.dg/vect/simd-10.cc  -std=c++17  scan-tree-dump-times vect "vectorized
[1-3] loops" 2
FAIL: g++.dg/vect/simd-10.cc  -std=c++20  scan-tree-dump-times vect "vectorized
[1-3] loops" 2

FAIL: gcc.dg/ira-loop-pressure.c scan-rtl-dump loop2_invariant "Decided to move
invariant"
FAIL: gcc.dg/pr41783.c scan-tree-dump pre "pretmp[^\\\\n]* = a_global_var;"
FAIL: gcc.dg/pr78138.c  (test for warnings, line 23)
FAIL: gcc.dg/tree-ssa/ifc-pr69489-1.c scan-tree-dump-times ifcvt "Applying
if-conversion" 1
FAIL: gcc.dg/tree-ssa/ifc-pr69489-1.c scan-tree-dump-times ifcvt "Invalid sum
of outgoing probabilities 200.0" 1
FAIL: gcc.dg/tree-ssa/ifc-pr69489-1.c scan-tree-dump-times ifcvt "Invalid sum
of incoming counts" 1
FAIL: gcc.dg/tree-ssa/ifc-pr69489-2.c scan-tree-dump-times ifcvt "Applying
if-conversion" 1
FAIL: gcc.dg/tree-ssa/ifc-pr69489-2.c scan-tree-dump-times ifcvt "Invalid sum
of outgoing probabilities 200.0" 1
FAIL: gcc.dg/tree-ssa/ifc-pr69489-2.c scan-tree-dump-times ifcvt "Invalid sum
of incoming counts" 1
FAIL: gcc.dg/tree-ssa/loadpre1.c scan-tree-dump-times pre "Eliminated: 1" 1
FAIL: gcc.dg/tree-ssa/loadpre10.c scan-tree-dump-times pre "Eliminated: 1" 1
FAIL: gcc.dg/tree-ssa/loadpre11.c scan-tree-dump-times pre "Eliminated: 1" 1
FAIL: gcc.dg/tree-ssa/loadpre12.c scan-tree-dump-times pre "Eliminated: 1" 1
FAIL: gcc.dg/tree-ssa/loadpre13.c scan-tree-dump-times pre "Eliminated: 1" 1
FAIL: gcc.dg/tree-ssa/loadpre14.c scan-tree-dump-times pre "Eliminated: 2" 1
FAIL: gcc.dg/tree-ssa/loadpre16.c scan-tree-dump-times pre "Eliminated: 1" 1
FAIL: gcc.dg/tree-ssa/loadpre2.c scan-tree-dump-times pre "Eliminated: 1" 1
FAIL: gcc.dg/tree-ssa/loadpre21.c scan-tree-dump-times pre "Eliminated: 1" 1
FAIL: gcc.dg/tree-ssa/loadpre23.c scan-tree-dump-times pre "Eliminated: 1" 1
FAIL: gcc.dg/tree-ssa/loadpre24.c scan-tree-dump-times pre "Eliminated: 1" 1
FAIL: gcc.dg/tree-ssa/loadpre25.c scan-tree-dump-times pre "Eliminated: 1" 1
FAIL: gcc.dg/tree-ssa/loadpre3.c scan-tree-dump-times pre "Eliminated: 2" 1
FAIL: gcc.dg/tree-ssa/loadpre4.c scan-tree-dump-times pre "Eliminated: 1" 1
FAIL: gcc.dg/tree-ssa/loadpre6.c scan-tree-dump-times pre "Eliminated: 1" 1
FAIL: gcc.dg/tree-ssa/loadpre6.c scan-tree-dump-times pre "Insertions: 1" 1
FAIL: gcc.dg/tree-ssa/pr21417.c scan-tree-dump-times thread2 "jump thread" 1
FAIL: gcc.dg/tree-ssa/pr23455.c scan-tree-dump-times pre "Eliminated: 3" 1
FAIL: gcc.dg/tree-ssa/pr35286.c scan-tree-dump-times pre "Eliminated: 2" 1
FAIL: gcc.dg/tree-ssa/pr35287.c scan-tree-dump-times pre "Eliminated: 3" 1
FAIL: gcc.dg/tree-ssa/pr43491.c scan-tree-dump-times optimized "= data_0;" 1
FAIL: gcc.dg/tree-ssa/pr47392.c scan-tree-dump pre "Eliminated: 1"
FAIL: gcc.dg/tree-ssa/predcom-1.c scan-tree-dump-times pcom "looparound ref" 1
FAIL: gcc.dg/tree-ssa/ssa-fre-45.c scan-tree-dump fre1 "return
y_\\\\d+\\\\(D\\\\);"
FAIL: gcc.dg/tree-ssa/ssa-hoist-4.c scan-tree-dump-times optimized "= \\\\*" 2
FAIL: gcc.dg/tree-ssa/ssa-hoist-4.c scan-tree-dump-times optimized "MAX_EXPR" 1
FAIL: gcc.dg/tree-ssa/ssa-hoist-8.c scan-tree-dump pre "HOIST inserted: 1"
FAIL: gcc.dg/tree-ssa/ssa-hoist-8.c scan-tree-dump-times pre " = mem;" 1
FAIL: gcc.dg/tree-ssa/ssa-hoist-9.c scan-tree-dump pre "HOIST inserted: 3"
FAIL: gcc.dg/tree-ssa/ssa-hoist-9.c scan-tree-dump-times pre " = \\\\*" 2
FAIL: gcc.dg/tree-ssa/ssa-hoist-9.c scan-tree-dump-times pre " = [^\\r\\n]*
\\\\+ [^\\r\\n]*;" 1
FAIL: gcc.dg/tree-ssa/ssa-pre-16.c scan-tree-dump-times pre "Eliminated: 1" 1
FAIL: gcc.dg/tree-ssa/ssa-pre-17.c scan-tree-dump pre "Eliminated: 1"
FAIL: gcc.dg/tree-ssa/ssa-pre-19.c scan-tree-dump pre "Eliminated: 3"
FAIL: gcc.dg/tree-ssa/ssa-pre-20.c scan-tree-dump pre "New PHIs: 2"
FAIL: gcc.dg/tree-ssa/ssa-pre-21.c scan-tree-dump-times pre "= \\\\*[^\\n;]*;"
2
FAIL: gcc.dg/tree-ssa/ssa-pre-23.c scan-tree-dump pre "Eliminated: 3"
FAIL: gcc.dg/tree-ssa/ssa-pre-25.c scan-tree-dump pre "Eliminated: 1"
FAIL: gcc.dg/tree-ssa/ssa-pre-29.c scan-tree-dump pre "Replaced hoist"
FAIL: gcc.dg/tree-ssa/ssa-pre-30.c scan-tree-dump-times pre "Replaced MEM" 3
FAIL: gcc.dg/tree-ssa/ssa-pre-34.c scan-tree-dump pre "Insertions: 1"
FAIL: gcc.dg/tree-ssa/ssa-pre-34.c scan-tree-dump pre "HOIST inserted: 1"
FAIL: gcc.dg/tree-ssa/ssa-pre-34.c scan-tree-dump pre "Eliminated: 3"
FAIL: gcc.dg/tree-ssa/ssa-pre-34.c scan-tree-dump-not optimized "foo"
FAIL: gcc.dg/vect/bb-slp-57.c -flto -ffat-lto-objects  scan-tree-dump-times
slp1 "transform load" 1
FAIL: gcc.dg/vect/bb-slp-57.c scan-tree-dump-times slp1 "transform load" 1
FAIL: gcc.dg/vect/pr56625.c scan-tree-dump-times vect "vectorized 1 loops" 1
...