perf annotate-data: Add stack operation pseudo type
A typical function prologue and epilogue include multiple stack operations to save and restore the current value of registers. On x86, it looks like below: push r15 push r14 push r13 push r12 ... pop r12 pop r13 pop r14 pop r15 ret As these all touches the stack memory region, chances are high that they appear in a memory profile data. But these are not used for any real purpose yet so it'd return no types. One of my profile type shows that non neglible portion of data came from the stack operations. It also seems GCC generates more stack operations than clang. Annotate Instruction stats total 264, ok 169 (64.0%), bad 95 (36.0%) Name : Good Bad ----------------------------------------------------------- movq : 49 27 movl : 24 9 popq : 0 19 <-- here cmpl : 17 2 addq : 14 1 cmpq : 12 2 cmpxchgl : 3 7 Instead of dealing them as unknown, let's create a seperate pseudo type to represent those stack operations separately. Reviewed-by: Ian Rogers <irogers@google.com> Cc: Stephane Eranian <eranian@google.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Link: https://lore.kernel.org/r/20240117062657.985479-5-namhyung@kernel.orgSigned-off-by: Namhyung Kim <namhyung@kernel.org>
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