Message ID | ZRxRdeneRzguiH9R@tucnak |
---|---|
State | New |
Headers | show |
Series | match.pd: Fix up a ? cst1 : cst2 regression on signed bool [PR111668] | expand |
On Tue, 3 Oct 2023, Jakub Jelinek wrote: > Hi! > > My relatively recent changes to these simplifiers to avoid > doing build_nonstandard_integer_type (primarily for BITINT_TYPE) > broke PR111668, a recurrence of the PR110487 bug. > I thought the build_nonstandard_integer_type isn't ever needed there, > but there is one special case where it is. > For the a ? -1 : 0 and a ? 0 : -1 simplifications there are actually > 3 different cases. One is for signed 1-bit precision types (signed > kind of implied from integer_all_onesp, because otherwise it would > match integer_onep earlier), where the simplifier wierdly was matching > them using the a ? powerof2cst : 0 -> a << (log2(powerof2cst)) > simplification and then another simplifier optimizing away the left shift > when log2(powerof2cst) was 0. Another one is signed BOOLEAN_TYPE with > precision > 1, where indeed we shouldn't be doing the negation in type, > because it isn't well defined in that type, the type only has 2 valid > values, 0 and -1. As an alternative, we could also e.g. cast to > signed 1-bit precision BOOLEAN_TYPE and then extend to type. > And the last case is what we were doing for types which have both 1 and -1 > (all all ones) as valid values (i.e. all signed/unsigned ENUMERAL_TYPEs, > INTEGRAL_TYPEs and BITINT_TYPEs with precision > 1). > > The following patch avoids the hops through << 0 for 1-bit precision > and uses build_nonstandard_integer_type solely for the BOOLEAN_TYPE types > (where we have a guarantee the precision is reasonably small, nothing ought > to be created 129+ bit precision BOOLEAN_TYPEs). > > Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? OK. > 2023-10-03 Jakub Jelinek <jakub@redhat.com> > > PR tree-optimization/111668 > * match.pd (a ? CST1 : CST2): Handle the a ? -1 : 0 and > a ? 0 : -1 cases before the powerof2cst cases and differentiate > between 1-bit precision types, larger precision boolean types > and other integral types. Fix comment pastos and formatting. > > --- gcc/match.pd.jj 2023-10-02 09:42:01.657836005 +0200 > +++ gcc/match.pd 2023-10-03 10:33:30.817614648 +0200 > @@ -5100,36 +5100,53 @@ (define_operator_list SYNC_FETCH_AND_AND > (switch > (if (integer_zerop (@2)) > (switch > - /* a ? 1 : 0 -> a if 0 and 1 are integral types. */ > + /* a ? 1 : 0 -> a if 0 and 1 are integral types. */ > (if (integer_onep (@1)) > (convert (convert:boolean_type_node @0))) > + /* a ? -1 : 0 -> -a. */ > + (if (INTEGRAL_TYPE_P (type) && integer_all_onesp (@1)) > + (if (TYPE_PRECISION (type) == 1) > + /* For signed 1-bit precision just cast bool to the type. */ > + (convert (convert:boolean_type_node @0)) > + (if (TREE_CODE (type) == BOOLEAN_TYPE) > + (with { > + tree intt = build_nonstandard_integer_type (TYPE_PRECISION (type), > + TYPE_UNSIGNED (type)); > + } > + (convert (negate (convert:intt (convert:boolean_type_node @0))))) > + (negate (convert:type (convert:boolean_type_node @0)))))) > /* a ? powerof2cst : 0 -> a << (log2(powerof2cst)) */ > (if (INTEGRAL_TYPE_P (type) && integer_pow2p (@1)) > (with { > tree shift = build_int_cst (integer_type_node, tree_log2 (@1)); > } > - (lshift (convert (convert:boolean_type_node @0)) { shift; }))) > - /* a ? -1 : 0 -> -a. No need to check the TYPE_PRECISION not being 1 > - here as the powerof2cst case above will handle that case correctly. */ > - (if (INTEGRAL_TYPE_P (type) && integer_all_onesp (@1)) > - (negate (convert:type (convert:boolean_type_node @0)))))) > + (lshift (convert (convert:boolean_type_node @0)) { shift; }))))) > (if (integer_zerop (@1)) > (switch > - /* a ? 0 : 1 -> !a. */ > + /* a ? 0 : 1 -> !a. */ > (if (integer_onep (@2)) > (convert (bit_xor (convert:boolean_type_node @0) { boolean_true_node; }))) > - /* a ? powerof2cst : 0 -> (!a) << (log2(powerof2cst)) */ > + /* a ? 0 : -1 -> -(!a). */ > + (if (INTEGRAL_TYPE_P (type) && integer_all_onesp (@2)) > + (if (TYPE_PRECISION (type) == 1) > + /* For signed 1-bit precision just cast bool to the type. */ > + (convert (bit_xor (convert:boolean_type_node @0) { boolean_true_node; })) > + (if (TREE_CODE (type) == BOOLEAN_TYPE) > + (with { > + tree intt = build_nonstandard_integer_type (TYPE_PRECISION (type), > + TYPE_UNSIGNED (type)); > + } > + (convert (negate (convert:intt (bit_xor (convert:boolean_type_node @0) > + { boolean_true_node; }))))) > + (negate (convert:type (bit_xor (convert:boolean_type_node @0) > + { boolean_true_node; })))))) > + /* a ? 0 : powerof2cst -> (!a) << (log2(powerof2cst)) */ > (if (INTEGRAL_TYPE_P (type) && integer_pow2p (@2)) > (with { > tree shift = build_int_cst (integer_type_node, tree_log2 (@2)); > } > (lshift (convert (bit_xor (convert:boolean_type_node @0) > - { boolean_true_node; })) { shift; }))) > - /* a ? -1 : 0 -> -(!a). No need to check the TYPE_PRECISION not being 1 > - here as the powerof2cst case above will handle that case correctly. */ > - (if (INTEGRAL_TYPE_P (type) && integer_all_onesp (@2)) > - (negate (convert:type (bit_xor (convert:boolean_type_node @0) > - { boolean_true_node; })))))))) > + { boolean_true_node; })) { shift; }))))))) > > /* (a > 1) ? 0 : (cast)a is the same as (cast)(a == 1) > for unsigned types. */ > > Jakub > >
--- gcc/match.pd.jj 2023-10-02 09:42:01.657836005 +0200 +++ gcc/match.pd 2023-10-03 10:33:30.817614648 +0200 @@ -5100,36 +5100,53 @@ (define_operator_list SYNC_FETCH_AND_AND (switch (if (integer_zerop (@2)) (switch - /* a ? 1 : 0 -> a if 0 and 1 are integral types. */ + /* a ? 1 : 0 -> a if 0 and 1 are integral types. */ (if (integer_onep (@1)) (convert (convert:boolean_type_node @0))) + /* a ? -1 : 0 -> -a. */ + (if (INTEGRAL_TYPE_P (type) && integer_all_onesp (@1)) + (if (TYPE_PRECISION (type) == 1) + /* For signed 1-bit precision just cast bool to the type. */ + (convert (convert:boolean_type_node @0)) + (if (TREE_CODE (type) == BOOLEAN_TYPE) + (with { + tree intt = build_nonstandard_integer_type (TYPE_PRECISION (type), + TYPE_UNSIGNED (type)); + } + (convert (negate (convert:intt (convert:boolean_type_node @0))))) + (negate (convert:type (convert:boolean_type_node @0)))))) /* a ? powerof2cst : 0 -> a << (log2(powerof2cst)) */ (if (INTEGRAL_TYPE_P (type) && integer_pow2p (@1)) (with { tree shift = build_int_cst (integer_type_node, tree_log2 (@1)); } - (lshift (convert (convert:boolean_type_node @0)) { shift; }))) - /* a ? -1 : 0 -> -a. No need to check the TYPE_PRECISION not being 1 - here as the powerof2cst case above will handle that case correctly. */ - (if (INTEGRAL_TYPE_P (type) && integer_all_onesp (@1)) - (negate (convert:type (convert:boolean_type_node @0)))))) + (lshift (convert (convert:boolean_type_node @0)) { shift; }))))) (if (integer_zerop (@1)) (switch - /* a ? 0 : 1 -> !a. */ + /* a ? 0 : 1 -> !a. */ (if (integer_onep (@2)) (convert (bit_xor (convert:boolean_type_node @0) { boolean_true_node; }))) - /* a ? powerof2cst : 0 -> (!a) << (log2(powerof2cst)) */ + /* a ? 0 : -1 -> -(!a). */ + (if (INTEGRAL_TYPE_P (type) && integer_all_onesp (@2)) + (if (TYPE_PRECISION (type) == 1) + /* For signed 1-bit precision just cast bool to the type. */ + (convert (bit_xor (convert:boolean_type_node @0) { boolean_true_node; })) + (if (TREE_CODE (type) == BOOLEAN_TYPE) + (with { + tree intt = build_nonstandard_integer_type (TYPE_PRECISION (type), + TYPE_UNSIGNED (type)); + } + (convert (negate (convert:intt (bit_xor (convert:boolean_type_node @0) + { boolean_true_node; }))))) + (negate (convert:type (bit_xor (convert:boolean_type_node @0) + { boolean_true_node; })))))) + /* a ? 0 : powerof2cst -> (!a) << (log2(powerof2cst)) */ (if (INTEGRAL_TYPE_P (type) && integer_pow2p (@2)) (with { tree shift = build_int_cst (integer_type_node, tree_log2 (@2)); } (lshift (convert (bit_xor (convert:boolean_type_node @0) - { boolean_true_node; })) { shift; }))) - /* a ? -1 : 0 -> -(!a). No need to check the TYPE_PRECISION not being 1 - here as the powerof2cst case above will handle that case correctly. */ - (if (INTEGRAL_TYPE_P (type) && integer_all_onesp (@2)) - (negate (convert:type (bit_xor (convert:boolean_type_node @0) - { boolean_true_node; })))))))) + { boolean_true_node; })) { shift; }))))))) /* (a > 1) ? 0 : (cast)a is the same as (cast)(a == 1) for unsigned types. */