diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 457c3385f8754b34657f212e223d2c590c68f754..38ae32110db492b6fda6db6d7ab925d02d9682a3 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2015-10-11 Jan Hubicka <hubicka@ucw.cz> + + * fold-const.c (operand_equal_p): Add code matching empty + constructors. + 2015-10-21 Eric Botcazou <ebotcazou@adacore.com> * tree.def (CEIL_DIV_EXPR, FLOOR_DIV_EXPR, ROUND_DIV_EXPR): Tweak diff --git a/gcc/fold-const.c b/gcc/fold-const.c index b7874a08c0b62acab3762d085de13f223557eb03..602ea240cb4b148442890fff3b0358556f87d4ff 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -2891,6 +2891,11 @@ operand_equal_p (const_tree arg0, const_tree arg1, unsigned int flags) return operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1, 0), flags | OEP_ADDRESS_OF | OEP_CONSTANT_ADDRESS_OF); + case CONSTRUCTOR: + /* In GIMPLE empty constructors are allowed in initializers of + aggregates. */ + return (!vec_safe_length (CONSTRUCTOR_ELTS (arg0)) + && !vec_safe_length (CONSTRUCTOR_ELTS (arg1))); default: break; } diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 9c76295c91689b74f21d6103d79448bce244912a..4637ae747e2059a2e273f7582128879ef4c5a6a3 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2015-10-11 Jan Hubicka <hubicka@ucw.cz> + + * gcc.dg/tree-ssa/operand-equal-1.c: Verify that empty constructors + are matched. + 2015-10-21 Richard Sandiford <richard.sandiford@arm.com> * gcc.dg/lto/20110201-1_0.c: Restrict to sqrt_insn targets. @@ -21,6 +26,7 @@ 2015-10-21 Marek Polacek <polacek@redhat.com> + PR c/68024 * gcc.dg/pr68024.c: New test. diff --git a/gcc/testsuite/gcc.dg/tree-ssa/operand-equal-1.c b/gcc/testsuite/gcc.dg/tree-ssa/operand-equal-1.c new file mode 100644 index 0000000000000000000000000000000000000000..09e9302ac16117f9d762af4437eedf605b83e9d3 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/operand-equal-1.c @@ -0,0 +1,8 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -fdump-tree-pre" } */ +struct a {int a,b;}; +struct a ret(int val) +{ + return val? (struct a){} : (struct a){}; +} +/* { dg-final { scan-tree-dump-not "if " "pre"} } */