gcc/testsuite/c-c++-common/torture/harden-cfr-tail.c

   1 /* { dg-do compile } */
   2 /* { dg-options "-fharden-control-flow-redundancy -fhardcfr-check-returning-calls -fno-hardcfr-check-exceptions -fdump-tree-hardcfr -ffat-lto-objects -Wno-return-type" } */
   3
   4 /* Check that we insert CFR checking so as to not disrupt tail calls.
   5    Mandatory tail calls are not available in C, and optimizing calls as tail
   6    calls only takes place after hardcfr, so we insert checking before calls
   7    followed by copies and return stmts with the same return value, that might
   8    (or might not) end up optimized to tail calls.  */
   9
  10 extern int g (int i);
  11
  12 int f1(int i) {
  13   /* Inline check before the returning call.  */
  14   return g (i);
  15 }
  16
  17 extern void g2 (int i);
  18
  19 void f2(int i) {
  20   /* Inline check before the returning call, that ignores the returned value,
  21      matching the value-less return.  */
  22   g2 (i);
  23   return;
  24 }
  25
  26 void f3(int i) {
  27   /* Inline check before the returning call.  */
  28   g (i);
  29 }
  30
  31 void f4(int i) {
  32   if (i)
  33     /* Out-of-line check before the returning call.  */
  34     return g2 (i);
  35   /* Out-of-line check before implicit return.  */
  36 }
  37
  38 int f5(int i) {
  39   /* Not regarded as a returning call, returning value other than callee's
  40      returned value.  */
  41   g (i);
  42   /* Inline check after the non-returning call.  */
  43   return i;
  44 }
  45
  46 /* Out-of-line checks in f4, before returning calls and before return.  */
  47 /* { dg-final { scan-tree-dump-times "hardcfr_check" 2 "hardcfr" } } */
  48 /* Inline checking in all other functions.  */
  49 /* { dg-final { scan-tree-dump-times "__builtin_trap" 4 "hardcfr" } } */
  50 /* Check before tail-call in all but f5, but f4 is out-of-line.  */
  51 /* { dg-final { scan-tree-dump-times "Inserting inline check before stmt" 3 "hardcfr" } } */
  52 /* { dg-final { scan-tree-dump-times "Inserting out-of-line check before stmt" 1 "hardcfr" } } */