diff options
| -rw-r--r-- | gcc/ChangeLog | 4 | ||||
| -rw-r--r-- | gcc/combine.c | 7 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 3 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.c-torture/execute/pr80501.c | 23 |
4 files changed, 35 insertions, 2 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 1138786..91e67b7 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,5 +1,9 @@ 2017-04-25 Jakub Jelinek <jakub@redhat.com> + PR rtl-optimization/80501 + * combine.c (make_compound_operation_int): Set subreg_code to SET + even for AND with mask of the sign bit of mode. + PR rtl-optimization/80500 * loop-unroll.c (combine_var_copies_in_loop_exit): Call copy_rtx on sum's initial value. diff --git a/gcc/combine.c b/gcc/combine.c index 87daa28..39ef3c6 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -8170,12 +8170,15 @@ make_compound_operation_int (machine_mode mode, rtx *x_ptr, || GET_CODE (inner) == SUBREG /* (subreg:SI (and:DI (reg:DI) (const_int 0x800000000)) 0) is (const_int 0), rather than - (subreg:SI (lshiftrt:DI (reg:DI) (const_int 35)) 0). */ + (subreg:SI (lshiftrt:DI (reg:DI) (const_int 35)) 0). + Similarly (subreg:QI (and:SI (reg:SI) (const_int 0x80)) 0) + for non-equality comparisons against 0 is not equivalent + to (subreg:QI (lshiftrt:SI (reg:SI) (const_int 7)) 0). */ || (GET_CODE (inner) == AND && CONST_INT_P (XEXP (inner, 1)) && GET_MODE_SIZE (mode) < GET_MODE_SIZE (GET_MODE (inner)) && exact_log2 (UINTVAL (XEXP (inner, 1))) - >= GET_MODE_BITSIZE (mode)))) + >= GET_MODE_BITSIZE (mode) - 1))) subreg_code = SET; tem = make_compound_operation (inner, subreg_code); diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 96f33f0..f4bede0 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,5 +1,8 @@ 2017-04-25 Jakub Jelinek <jakub@redhat.com> + PR rtl-optimization/80501 + * gcc.c-torture/execute/pr80501.c: New test. + PR rtl-optimization/80500 * gcc.dg/pr80500.c: New test. diff --git a/gcc/testsuite/gcc.c-torture/execute/pr80501.c b/gcc/testsuite/gcc.c-torture/execute/pr80501.c new file mode 100644 index 0000000..0a33e1f --- /dev/null +++ b/gcc/testsuite/gcc.c-torture/execute/pr80501.c @@ -0,0 +1,23 @@ +/* PR rtl-optimization/80501 */ + +signed char v = 0; + +static signed char +foo (int x, int y) +{ + return x << y; +} + +__attribute__((noinline, noclone)) int +bar (void) +{ + return foo (v >= 0, __CHAR_BIT__ - 1) >= 1; +} + +int +main () +{ + if (sizeof (int) > sizeof (char) && bar () != 0) + __builtin_abort (); + return 0; +} |