| Message ID | ZQlMfsN2tNELdv0B@tucnak |
|---|---|
| State | New |
| Headers | show |
| Series | v2: small _BitInt tweaks | expand |
On Tue, 19 Sep 2023, Jakub Jelinek wrote: > Hi! > > On Tue, Sep 12, 2023 at 05:27:30PM +0000, Joseph Myers wrote: > > On Tue, 12 Sep 2023, Jakub Jelinek via Gcc-patches wrote: > > > > > And by ensuring we never create 1-bit signed BITINT_TYPE e.g. the backends > > > don't need to worry about them. > > > > > > But I admit I don't feel strongly about that. > > > > > > Joseph, what do you think about this? > > > > I think it's appropriate to avoid 1-bit signed BITINT_TYPE consistently. > > Here is a patch which does that. In addition to the previously changed two > hunks it also adds a checking assertion that we don't create > signed _BitInt(0), unsigned _BitInt(0) or signed _BitInt(1) types. > > Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? OK. Thanks, Richard. > 2023-09-18 Jakub Jelinek <jakub@redhat.com> > > gcc/ > * tree.cc (build_bitint_type): Assert precision is not 0, or > for signed types 1. > (signed_or_unsigned_type_for): Return INTEGER_TYPE for signed variant > of unsigned _BitInt(1). > gcc/c-family/ > * c-common.cc (c_common_signed_or_unsigned_type): Return INTEGER_TYPE > for signed variant of unsigned _BitInt(1). > > --- gcc/tree.cc.jj 2023-09-11 17:01:17.612714178 +0200 > +++ gcc/tree.cc 2023-09-18 12:36:37.598912717 +0200 > @@ -7179,6 +7179,8 @@ build_bitint_type (unsigned HOST_WIDE_IN > { > tree itype, ret; > > + gcc_checking_assert (precision >= 1 + !unsignedp); > + > if (unsignedp) > unsignedp = MAX_INT_CACHED_PREC + 1; > > @@ -11096,7 +11098,7 @@ signed_or_unsigned_type_for (int unsigne > else > return NULL_TREE; > > - if (TREE_CODE (type) == BITINT_TYPE) > + if (TREE_CODE (type) == BITINT_TYPE && (unsignedp || bits > 1)) > return build_bitint_type (bits, unsignedp); > return build_nonstandard_integer_type (bits, unsignedp); > } > --- gcc/c-family/c-common.cc.jj 2023-09-11 17:01:17.517715431 +0200 > +++ gcc/c-family/c-common.cc 2023-09-18 12:35:06.829126858 +0200 > @@ -2739,7 +2739,9 @@ c_common_signed_or_unsigned_type (int un > || TYPE_UNSIGNED (type) == unsignedp) > return type; > > - if (TREE_CODE (type) == BITINT_TYPE) > + if (TREE_CODE (type) == BITINT_TYPE > + /* signed _BitInt(1) is invalid, avoid creating that. */ > + && (unsignedp || TYPE_PRECISION (type) > 1)) > return build_bitint_type (TYPE_PRECISION (type), unsignedp); > > #define TYPE_OK(node) \ > > > Jakub > >
--- gcc/tree.cc.jj 2023-09-11 17:01:17.612714178 +0200 +++ gcc/tree.cc 2023-09-18 12:36:37.598912717 +0200 @@ -7179,6 +7179,8 @@ build_bitint_type (unsigned HOST_WIDE_IN { tree itype, ret; + gcc_checking_assert (precision >= 1 + !unsignedp); + if (unsignedp) unsignedp = MAX_INT_CACHED_PREC + 1; @@ -11096,7 +11098,7 @@ signed_or_unsigned_type_for (int unsigne else return NULL_TREE; - if (TREE_CODE (type) == BITINT_TYPE) + if (TREE_CODE (type) == BITINT_TYPE && (unsignedp || bits > 1)) return build_bitint_type (bits, unsignedp); return build_nonstandard_integer_type (bits, unsignedp); } --- gcc/c-family/c-common.cc.jj 2023-09-11 17:01:17.517715431 +0200 +++ gcc/c-family/c-common.cc 2023-09-18 12:35:06.829126858 +0200 @@ -2739,7 +2739,9 @@ c_common_signed_or_unsigned_type (int un || TYPE_UNSIGNED (type) == unsignedp) return type; - if (TREE_CODE (type) == BITINT_TYPE) + if (TREE_CODE (type) == BITINT_TYPE + /* signed _BitInt(1) is invalid, avoid creating that. */ + && (unsignedp || TYPE_PRECISION (type) > 1)) return build_bitint_type (TYPE_PRECISION (type), unsignedp); #define TYPE_OK(node) \