| /* The function below expands to a loop whose latch block starts with |
| a PHI node and the corresponding debug stmt. In RTL, there are no |
| PHI nodes, but the debug insn that references the incoming k |
| remains, even though one of the incoming edges has it |
| uninitialized. After unrolling, however, the debug insn becomes |
| unconditional, and this exposed a problem in the webizer. Because |
| DF doesn't combine the uses of an uninitialized pseudo into a |
| single UD chain, we created a separate web for each use. |
| Allocating separate registers or stack slots for each uninitialized |
| use is wasteful, but the problem became more apparent in |
| -fcompare-debug tests: register numbers went out of sync, and could |
| have caused codegen differences depending on whether or not the |
| debug insns were present. The fix was to arrange for web to |
| combine uninitialized uses into a single web. */ |
| |
| /* { dg-do compile } */ |
| /* { dg-options "-g -O1 -funroll-loops -fcompare-debug" } */ |
| /* { dg-xfail-if "AIX compare debug" { powerpc-ibm-aix* } } */ |
| |
| void foo() |
| { |
| unsigned k; |
| while (--k > 0); |
| } |
