diff options
Diffstat (limited to 'gcc/testsuite/gcc.target/avr/pr46779-1.c')
-rw-r--r-- | gcc/testsuite/gcc.target/avr/pr46779-1.c | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/gcc/testsuite/gcc.target/avr/pr46779-1.c b/gcc/testsuite/gcc.target/avr/pr46779-1.c new file mode 100644 index 00000000000..24522f175be --- /dev/null +++ b/gcc/testsuite/gcc.target/avr/pr46779-1.c @@ -0,0 +1,51 @@ +/* { dg-do run } */ +/* { dg-options "-Os -fsplit-wide-types" } */ + +/* This testcase should uncover bugs like + PR46779 + PR45291 + PR41894 + + The inline asm just serves to direct y into the Y register. + Otherwise, it is hard to write a "stable" test case that + also fails with slight variations in source code, middle- resp. + backend. + + The problem is that Y is also the frame-pointer, and + avr.c:avr_hard_regno_mode_ok disallows QI to get in Y-reg. + However, the y.a = 0 generates a + (set (subreg:QI (reg:HI pseudo)) ...) + where pseudo gets allocated to Y. + + Reload fails to generate the right spill. +*/ + +#include <stdlib.h> + +struct S +{ + unsigned char a, b; +} ab = {12, 34}; + +void yoo (struct S y) +{ + __asm volatile ("ldi %B0, 56" : "+y" (y)); + y.a = 0; + __asm volatile ("; y = %0" : "+y" (y)); + ab = y; +} + +int main () +{ + yoo (ab); + + if (ab.a != 0) + abort(); + + if (ab.b != 56) + abort(); + + exit (0); + + return 0; +} |