[cfe-commits] r148243 - /cfe/trunk/lib/CodeGen/CGStmt.cpp

[Aaron Ballman]

On Mon, Jan 16, 2012 at 1:12 PM, Eli Friedman <eli.friedman at gmail.com> wrote:
> On Mon, Jan 16, 2012 at 10:26 AM, jahanian <fjahanian at apple.com> wrote:
>>
>> On Jan 16, 2012, at 10:20 AM, Eli Friedman wrote:
>>
>> On Mon, Jan 16, 2012 at 10:14 AM, Aaron Ballman <aaron at aaronballman.com>
>> wrote:
>>
>> On Mon, Jan 16, 2012 at 11:56 AM, David Blaikie <dblaikie at gmail.com> wrote:
>>
>>
>> I'll come up with some test cases to check this out tonight, and pass
>>
>> them along to verify I understand the concerns properly.
>>
>>
>> Okay... I'm specifically concerned about the code generation for
>> non-constant-folded-switch containing a constant-folded switch.
>>
>>
>> Just committed a test case which seems to handle this correctly.
>
> Managed to come up with the testcase I was thinking of:
>
> #include <stdio.h>
> int test(int val){
>  switch (val) {
>  case 4:
>    do {
>      switch (6) {
>        case 6: do { case 5: printf("bad\n"); } while (0);
>      };
>    } while (0);
>  }
>  return 0;
> }
>
> int main(void) {
>  return test(5);
> }

I just had the chance to try out this test case, and you're right, it
does produce the wrong code in this instance.  It emits the case 5
against the outer switch (because SwitchInsn is non-null).

I'll think about ways to handle this, but if anyone has suggestions
they'd like to share, I'm all ears.

~Aaron