Macro fusion merges two instructions to a single micro-op. Intel
core platform performs this hardware optimization under limited
circumstances. For example, CMP + JCC can be "fused" and executed
/retired together. While with sampling this can result in the
sample sometimes being on the JCC and sometimes on the CMP.
So for the fused instruction pair, they could be considered
together.
In general, the fused instruction pairs are:
cmp/test/add/sub/and/inc/dec + jcc.
This patch series marks the case clearly by joining the fused
instruction pair in the arrow of the jump.
For example:
│ ┌──cmpl $0x0,argp_program_version_hook
81.93 │ │──je 20
│ │ lock cmpxchg %esi,0x38a9a4(%rip)
│ │↓ jne 29
│ │↓ jmp 43
11.47 │20:└─→cmpxch %esi,0x38a999(%rip)
Jin Yao (2):
perf report: Check for fused instruction pair
perf report: Implement visual marker for macro fusion in annotate
tools/perf/arch/x86/util/Build | 1 +
tools/perf/arch/x86/util/fused.c | 20 ++++++++++++++++++++
tools/perf/ui/browser.c | 27 +++++++++++++++++++++++++++
tools/perf/ui/browser.h | 2 ++
tools/perf/ui/browsers/annotate.c | 30 ++++++++++++++++++++++++++++++
tools/perf/util/Build | 1 +
tools/perf/util/annotate.c | 5 +++++
tools/perf/util/annotate.h | 1 +
tools/perf/util/fused.c | 11 +++++++++++
tools/perf/util/fused.h | 8 ++++++++
10 files changed, 106 insertions(+)
create mode 100644 tools/perf/arch/x86/util/fused.c
create mode 100644 tools/perf/util/fused.c
create mode 100644 tools/perf/util/fused.h
--
2.7.4
