Dear Richard Guenther,
In my pass code, my printf code use ivvarincedloop from API.
create_iv (build_int_cst_type (integer_type_node, 0),
build_int_cst_type (integer_type_node, 1),
ivvarloop, loop, &bsi, insert_after,
&ivvarloop, &ivvarincedloop);
How can I use the variable generated by create_iv API
(ivvarincedloop) in my later printf statement?
My pass code in the attachment in last email.
Thank you.
Fern
On Fri, Jul 11, 2008 at 11:29 AM, Richard Guenther
<[EMAIL PROTECTED]> wrote:
> On Fri, Jul 11, 2008 at 5:23 PM, Fern Moon <[EMAIL PROTECTED]> wrote:
>> Dear sir,
>>
>> I write a pass to instrument loops to count runtime number of iterations.
>> I insert a variable in each loop by create_tmp_var() and output
>> the results by inserting a printf function at the exit edge of loop.
>> The code is the attachment.
>>
>> The problem is that for the loops without switch statement inside, my
>> pass works well,
>> but for loops with switch statement inside, my final printf can not
>> catch the correct
>> runtime value of my instrumented variable. In some later pass, the pass will
>> remove my variable increasing statement in loops as a dead code. My
>> final instrumentation will
>> output the initial value only. I attached a simple "hello" world program and
>> dump output tree for it after my pass.
>>
>>
>> Thank you for your help.
>>
>> Fern
>>
>>
>> ====== hello world test program======
>> ===============================
>> int main(int argc, char * argv[] )
>> {
>> int i;
>>
>> for (i=0; i<10; i++) {
>>
>> printf("Hello World\n");
>> switch(i) {
>> case 1:
>> printf("Hello World 1\n");
>> break;
>> }
>>
>>
>> }
>>
>> =========dump tree file of my pass===============
>>
>> ;; Function main (main)
>>
>>
>> SSA replacement table
>> N_i -> { O_1 ... O_j } means that N_i replaces O_1, ..., O_j
>>
>> looptest1.25_1 -> { looptest1.25_6 }
>>
>> Number of virtual NEW -> OLD mappings: 0
>> Number of real NEW -> OLD mappings: 1
>> Number of total NEW -> OLD mappings: 1
>>
>> Number of virtual symbols: 0
>>
>>
>> Incremental SSA update started at block: 6
>>
>> Number of blocks in CFG: 9
>> Number of blocks to update: 3 ( 33%)
>>
>>
>>
>> ssa loop profile
>> main (argc, argv)
>> {
>> int looptest1.25;
>> int prephitmp.20;
>> int pretmp.19;
>> int i;
>>
>> <bb 2>:
>> __builtin_puts (&"Hello World"[0]);
>> goto <bb 6>;
>>
>> <bb 3>:
>> __builtin_puts (&"Hello World"[0]);
>> switch (i_3)
>> {
>> case 1: goto <L1>;
>> default : goto <L7>;
>> }
>>
>> <L7>:;
>> goto <bb 5> (<L6>);
>>
>> <L1>:;
>> __builtin_puts (&"Hello World 1"[0]);
>>
>> # i_5 = PHI <1(4), i_3(8)>
>> <L6>:;
>> looptest1.25_6 = looptest1.25_4 + 1;
>>
>> <bb 6>:
>> # looptest1.25_4 = PHI <looptest1.25_6(5), 0(2)>
>> # i_7 = PHI <i_5(5), 0(2)>
>> i_3 = i_7 + 1;
>> if (i_3 <= 9)
>> goto <bb 3>;
>> else
>> goto <bb 7>;
>>
>> <bb 7>:
>> # looptest1.25_1 = PHI <looptest1.25_8(D)(6)>
>> printf (&"main loopid: 1 counter: %d\n"[0], looptest1.25_1);
>
> This uses the uninitialized default-definition of looptest1.25, looptest25_4
> is
> unused and DCEd.
>
> Richard.
>
