Displaying 2 results from an estimated 2 matches for "bpf_output".
llvm bpf debug info. Re: [RFC PATCH v4 3/3] bpf: Introduce function for outputing data to perf event
2015 Aug 12
2
llvm bpf debug info. Re: [RFC PATCH v4 3/3] bpf: Introduce function for outputing data to perf event
...cific intrinsic. However, LLVM isolates backend and
frontend, and there's no way to pass language level type information
to backend code.
Think about a program like this:
struct strA { int a; }
struct strB { int b; }
int func() {
struct strA a;
struct strB b;
a.a = 1;
b.b = 2;
bpf_output(gettype(a), &a);
bpf_output(gettype(b), &b);
return 0;
}
BPF backend can't (and needn't) tell the difference between local
variables a and b in theory. In LLVM implementation, it filters type
information out using ComputeValueVTs(). Please have a look at
SelectionDAGBuilder:...
llvm bpf debug info. Re: [RFC PATCH v4 3/3] bpf: Introduce function for outputing data to perf event
2015 Aug 12
3
llvm bpf debug info. Re: [RFC PATCH v4 3/3] bpf: Introduce function for outputing data to perf event
...4:43AM +0800, Wangnan (F) via llvm-dev wrote:
>> Think about a program like this:
>>
>> struct strA { int a; }
>> struct strB { int b; }
>> int func() {
>> struct strA a;
>> struct strB b;
>>
>> a.a = 1;
>> b.b = 2;
>> bpf_output(gettype(a), &a);
>> bpf_output(gettype(b), &b);
>> return 0;
>> }
>>
>> BPF backend can't (and needn't) tell the difference between local
>> variables a and b in theory. In LLVM implementation, it filters type
>> information out using...