From 554fd8c5195424bdbcabf5de30fdc183aba391bd Mon Sep 17 00:00:00 2001 From: upstream source tree Date: Sun, 15 Mar 2015 20:14:05 -0400 Subject: obtained gcc-4.6.4.tar.bz2 from upstream website; verified gcc-4.6.4.tar.bz2.sig; imported gcc-4.6.4 source tree from verified upstream tarball. downloading a git-generated archive based on the 'upstream' tag should provide you with a source tree that is binary identical to the one extracted from the above tarball. if you have obtained the source via the command 'git clone', however, do note that line-endings of files in your working directory might differ from line-endings of the respective files in the upstream repository. --- gcc/testsuite/gcc.dg/nrv4.c | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) create mode 100644 gcc/testsuite/gcc.dg/nrv4.c (limited to 'gcc/testsuite/gcc.dg/nrv4.c') diff --git a/gcc/testsuite/gcc.dg/nrv4.c b/gcc/testsuite/gcc.dg/nrv4.c new file mode 100644 index 000000000..e213d860e --- /dev/null +++ b/gcc/testsuite/gcc.dg/nrv4.c @@ -0,0 +1,33 @@ +/* Verify that NRV optimizations are prohibited when the LHS is an + indirect reference to something that may be call-clobbered. */ +/* { dg-do compile } */ +/* { dg-options "-O -fdump-tree-optimized" } */ + +typedef struct { int x[20]; void *y; } S; +S nrv_candidate (void); +void use_result (S); +void make_escape (S *); +S global_S; +void foo (void) +{ + S *result; + S local_S; + + /* We can't perform return slot optimization because global_S is + global and may be clobbered by nrv_candidate. */ + result = &global_S; + *result = nrv_candidate (); + use_result (*result); + + /* We can't perform return slot optimization because local_S is + call_clobbered (its address escapes prior to invoking + nrv_candidate). */ + make_escape (&local_S); + result = &local_S; + *result = nrv_candidate (); + use_result (*result); +} + +/* { dg-final { scan-tree-dump-times "return slot optimization" 0 "optimized" } } */ +/* { dg-final { cleanup-tree-dump "optimized" } } */ + -- cgit v1.2.3