From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2153) id B2C183A77C0C; Fri, 23 Apr 2021 10:52:32 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org B2C183A77C0C Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Jakub Jelinek To: gcc-cvs@gcc.gnu.org Subject: [gcc(refs/vendors/redhat/heads/gcc-8-branch)] tree-cfg: Allow enum types as result of POINTER_DIFF_EXPR [PR98556] X-Act-Checkin: gcc X-Git-Author: Jakub Jelinek X-Git-Refname: refs/vendors/redhat/heads/gcc-8-branch X-Git-Oldrev: c05a308971e6d94deb50e7cc0c324bc20123b425 X-Git-Newrev: d033427039789102a65b3dcb4aa5c64a757b762f Message-Id: <20210423105232.B2C183A77C0C@sourceware.org> Date: Fri, 23 Apr 2021 10:52:32 +0000 (GMT) X-BeenThere: gcc-cvs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 23 Apr 2021 10:52:32 -0000 https://gcc.gnu.org/g:d033427039789102a65b3dcb4aa5c64a757b762f commit d033427039789102a65b3dcb4aa5c64a757b762f Author: Jakub Jelinek Date: Sat Jan 9 10:49:38 2021 +0100 tree-cfg: Allow enum types as result of POINTER_DIFF_EXPR [PR98556] As conversions between signed integers and signed enums with the same precision are useless in GIMPLE, it seems strange that we require that POINTER_DIFF_EXPR result must be INTEGER_TYPE. If we really wanted to require that, we'd need to change the gimplifier to ensure that, which it isn't the case on the following testcase. What is going on during the gimplification is that when we have the (enum T) (p - q) cast, it is stripped through /* Strip away as many useless type conversions as possible at the toplevel. */ STRIP_USELESS_TYPE_CONVERSION (*expr_p); and when the MODIFY_EXPR is gimplified, the *to_p has enum T type, while *from_p has intptr_t type and as there is no conversion in between, we just create GIMPLE_ASSIGN from that. 2021-01-09 Jakub Jelinek PR c++/98556 * tree-cfg.c (verify_gimple_assign_binary): Allow lhs of POINTER_DIFF_EXPR to be any integral type. * c-c++-common/pr98556.c: New test. (cherry picked from commit 0188eab844eacda5edc6257771edb771844ae069) Diff: --- gcc/testsuite/c-c++-common/pr98556.c | 11 +++++++++++ gcc/tree-cfg.c | 2 +- 2 files changed, 12 insertions(+), 1 deletion(-) diff --git a/gcc/testsuite/c-c++-common/pr98556.c b/gcc/testsuite/c-c++-common/pr98556.c new file mode 100644 index 00000000000..865957bf353 --- /dev/null +++ b/gcc/testsuite/c-c++-common/pr98556.c @@ -0,0 +1,11 @@ +/* PR c++/98556 */ +/* { dg-do compile } */ +/* { dg-options "-O0" } */ + +enum T { E = -__LONG_MAX__ - 1 }; + +enum T +foo (char *p, char *q) +{ + return (enum T) (p - q); +} diff --git a/gcc/tree-cfg.c b/gcc/tree-cfg.c index 6a2cf8b01ff..4d144fcbd43 100644 --- a/gcc/tree-cfg.c +++ b/gcc/tree-cfg.c @@ -4163,7 +4163,7 @@ verify_gimple_assign_binary (gassign *stmt) /* Because we special-case pointers to void we allow difference of arbitrary pointers with the same mode. */ || TYPE_MODE (rhs1_type) != TYPE_MODE (rhs2_type) - || TREE_CODE (lhs_type) != INTEGER_TYPE + || !INTEGRAL_TYPE_P (lhs_type) || TYPE_UNSIGNED (lhs_type) || TYPE_PRECISION (lhs_type) != TYPE_PRECISION (rhs1_type)) {