Files
clang-p2996/llvm/test/tools/llvm-profgen/Inputs/noinline-cs-noprobe.perfscript
wlei c681400b25 [CSSPGO][llvm-profgen] Virtual unwinding with pseudo probe
This change extends virtual unwinder to support pseudo probe in llvm-profgen. Please refer https://groups.google.com/g/llvm-dev/c/1p1rdYbL93s and https://reviews.llvm.org/D89707 for more context about CSSPGO and llvm-profgen.

**Implementation**

- Added `ProbeBasedCtxKey` derived from `ContextKey` for sample counter aggregation. As we need string splitting to infer the profile for callee function, string based context introduces more string handling overhead, here we just use probe pointer based context.
- For linear unwinding, as inline context is encoded in each pseudo probe, we don't need to go through each instruction to extract range sharing same inliner. So just record the range for the context.
- For probe based context, we should ignore the top frame probe since it will be extracted from the address range. we defer the extraction in `ProfileGeneration`.
- Added `PseudoProbeProfileGenerator` for pseudo probe based profile generation.
- Some helper function to get pseduo probe info(call probe, inline context) from profiled binary.
- Added regression test for unwinder's output

The pseudo probe based profile generation will be in the upcoming patch.

Test Plan:

ninja & ninja check-llvm

Differential Revision: https://reviews.llvm.org/D92896
2021-01-13 11:02:58 -08:00

24 lines
1.6 KiB
Plaintext

PERF_RECORD_MMAP2 2854748/2854748: [0x400000(0x1000) @ 0 00:1d 123291722 526021]: r-xp /home/noinline-cs-noprobe.perfbin
4005dc
400634
400684
7f68c5788793
0x4005c8/0x4005dc/P/-/-/0 0x40062f/0x4005b0/P/-/-/0 0x400645/0x4005ff/P/-/-/0 0x400637/0x400645/P/-/-/0 0x4005e9/0x400634/P/-/-/0 0x4005d7/0x4005e5/P/-/-/0 0x40062f/0x4005b0/P/-/-/0 0x400645/0x4005ff/P/-/-/0 0x400637/0x400645/P/-/-/0 0x4005e9/0x400634/P/-/-/0 0x4005d7/0x4005e5/P/-/-/0 0x40062f/0x4005b0/P/-/-/0 0x400645/0x4005ff/P/-/-/0 0x400637/0x400645/P/-/-/0 0x4005e9/0x400634/P/-/-/0 0x4005c8/0x4005dc/P/-/-/0
// Test for leaf frame ending up in prolog
4005b0
400684
7f68c5788793
0x40062f/0x4005b0/P/-/-/0 0x400645/0x4005ff/P/-/-/0 0x400637/0x400645/P/-/-/0 0x4005e9/0x400634/P/-/-/0 0x4005c8/0x4005dc/P/-/-/0 0x40062f/0x4005b0/P/-/-/0 0x400645/0x4005ff/P/-/-/0 0x400637/0x400645/P/-/-/0 0x4005e9/0x400634/P/-/-/0 0x4005d7/0x4005e5/P/-/-/0 0x40062f/0x4005b0/P/-/-/0 0x400645/0x4005ff/P/-/-/0 0x400637/0x400645/P/-/-/0 0x4005e9/0x400634/P/-/-/0 0x4005d7/0x4005e5/P/-/-/0 0x40062f/0x4005b0/P/-/-/0
// Call stack:
// 4005b0 -> start addr of bar
// 400684 -> address in main
// LBR Entry: | Source | Target
// 0x40062f/0x4005b0/P/-/-/0 | callq -132 <bar> | start addr of bar
// 0x400645/0x4005ff/P/-/-/0 | jmp -75 <foo+0xf> | movl -8(%rbp), %eax
// 0x400637/0x400645/P/-/-/0 | jmp 9 <foo+0x55> | jmp -75 <foo+0xf>
// 0x4005e9/0x400634/P/-/-/0 | (bar)retq | next addr of [callq -132 <bar>]
// 0x4005d7/0x4005e5/P/-/-/0 | jmp 9 <bar+0x35> | movl -4(%rbp), %eax