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Commit 85c5efcf authored by Andrew Pinski's avatar Andrew Pinski
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MATCH: (convert)(zero_one !=/== 0/1) for outer type and zero_one type are the same

When I moved two_value to match.pd, I removed the check for the {0,+-1}
as I had placed it after the {0,+-1} case for cond in match.pd.
In the case of {0,+-1} and non boolean, before we would optmize those
case to just `(convert)a` but after we would get `(convert)(a != 0)`
which was not handled anyways to just `(convert)a`.
So this adds a pattern to match `(convert)(zeroone != 0)` and simplify
to `(convert)zeroone`.

Also this optimizes (convert)(zeroone == 0) into (zeroone^1) if the
type match. Removing the opposite transformation from fold.
The opposite transformation was added with
https://gcc.gnu.org/pipermail/gcc-patches/2006-February/190514.html


It is no longer considered the canonicalization either, even VRP will
transform it back into `(~a) & 1` so removing it is a good idea.

Note the testcase pr69270.c needed a slight update due to not matching
exactly a scan pattern, this update makes it more robust and will match
before and afterwards and if there are other changes in this area too.

Note the testcase gcc.target/i386/pr110790-2.c needs a slight update
for better code generation in LP64 bit mode.

Bootstrapped and tested on x86_64-linux-gnu with no regressions.

gcc/ChangeLog:

	PR tree-optimization/111972
	PR tree-optimization/110637
	* match.pd (`(convert)(zeroone !=/== CST)`): Match
	and simplify to ((convert)zeroone){,^1}.
	* fold-const.cc (fold_binary_loc): Remove
	transformation of `(~a) & 1` and `(a ^ 1) & 1`
	into `(convert)(a == 0)`.

gcc/testsuite/ChangeLog:

	* gcc.dg/tree-ssa/pr110637-1.c: New test.
	* gcc.dg/tree-ssa/pr110637-2.c: New test.
	* gcc.dg/tree-ssa/pr110637-3.c: New test.
	* gcc.dg/tree-ssa/pr111972-1.c: New test.
	* gcc.dg/tree-ssa/pr69270.c: Update testcase.
	* gcc.target/i386/pr110790-2.c: Update testcase.
	* gcc.dg/fold-even-1.c: Removed.

Signed-off-by: default avatarAndrew Pinski <quic_apinski@quicinc.com>
parent 4eaaf7f5
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