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| author | Jan Hubicka <jh@suse.cz> | 2021-11-19 18:09:13 +0100 |
|---|---|---|
| committer | Jan Hubicka <jh@suse.cz> | 2021-11-19 18:09:13 +0100 |
| commit | ada63d56beb0e535d35b165b55f85e29a0b36929 (patch) | |
| tree | b809bfa4f6a962e625f2c437130a2eb60e0ba7d4 | |
| parent | 16137fbb9256ef365dd498d39024eb33de1a4cd8 (diff) | |
| download | gcc-ada63d56beb0e535d35b165b55f85e29a0b36929.zip gcc-ada63d56beb0e535d35b165b55f85e29a0b36929.tar.gz gcc-ada63d56beb0e535d35b165b55f85e29a0b36929.tar.bz2 | |
Use modref even for nested functions in ref_maybe_used_by_call_p_1
Remove test for function not having call chain guarding modref use in
ref_maybe_used_by_call_p_1. It never made sense since modref treats call chain
accesses explicitly. It was however copied from earlier check for ECF_CONST
(which seems dubious too, but I would like to discuss it independelty).
This enables us to detect that memory pointed to static chain (or parts of it)
are unused by the function.
lto-bootstrapped-regtested all lanugages on x86_64-linux.
gcc/ChangeLog:
2021-11-19 Jan Hubicka <hubicka@ucw.cz>
* tree-ssa-alias.c (ref_maybe_used_by_call_p_1): Do not guard modref
by !gimple_call_chain.
gcc/testsuite/ChangeLog:
2021-11-19 Jan Hubicka <hubicka@ucw.cz>
* gcc.dg/tree-ssa/modref-dse-6.c: New test.
| -rw-r--r-- | gcc/testsuite/gcc.dg/tree-ssa/modref-dse-6.c | 23 | ||||
| -rw-r--r-- | gcc/tree-ssa-alias.c | 2 |
2 files changed, 24 insertions, 1 deletions
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/modref-dse-6.c b/gcc/testsuite/gcc.dg/tree-ssa/modref-dse-6.c new file mode 100644 index 0000000..d1e45a8 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/modref-dse-6.c @@ -0,0 +1,23 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -fdump-tree-optimized" } */ +int +main() +{ + int a,b; + __attribute__ ((noinline)) + void kill_me() + { + a=1234; + b=2234; + } + a=0; + b=1234; + __attribute__ ((noinline)) + int reta() + { + return a; + } + return reta(); +} +/* { dg-final { scan-tree-dump-not "kill_me" "optimized" } } */ +/* { dg-final { scan-tree-dump-not "1234" "optimized" } } */ diff --git a/gcc/tree-ssa-alias.c b/gcc/tree-ssa-alias.c index 02bbc87..cd6a0b2 100644 --- a/gcc/tree-ssa-alias.c +++ b/gcc/tree-ssa-alias.c @@ -2755,7 +2755,7 @@ ref_maybe_used_by_call_p_1 (gcall *call, ao_ref *ref, bool tbaa_p) callee = gimple_call_fndecl (call); - if (!gimple_call_chain (call) && callee != NULL_TREE) + if (callee != NULL_TREE) { struct cgraph_node *node = cgraph_node::get (callee); /* We can not safely optimize based on summary of calle if it does |