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[PATCH v4 0/2] perf report: Implement visual marker for macro fusion in annotate

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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.

On Nehalem, fused instruction pairs:
cmp/test + jcc.

On other new CPU:
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)

Change-log:
-----------
v4: Move the CPU model checking to symbol__disassemble and save
    the family/model in arch structure. It avoids checking everytime
    when display the jump arrows.

    The patch set is still performing the fused checking when user
    moves the cursor on the jump instruction.

v3: 1.  Add checking for Nehalem (CMP, TEST). For other newer
        Intel CPUs just check it by default (CMP, TEST, ADD,
        SUB, AND, INC, DEC).

    2.  Use Arnaldo's fix to let the display be better

v2: According to Arnaldo's comments, remove the weak function and
    use an arch-specific function instead to check fused instruction
    pair.

v1: Inital post

Jin Yao (2):
  perf util: Check for fused instruction
  perf report: Implement visual marker for macro fusion in annotate

 tools/perf/arch/x86/annotate/instructions.c | 46 +++++++++++++++++++++++++++++
 tools/perf/builtin-top.c                    |  2 +-
 tools/perf/ui/browser.c                     | 29 ++++++++++++++++++
 tools/perf/ui/browser.h                     |  2 ++
 tools/perf/ui/browsers/annotate.c           | 30 ++++++++++++++++++-
 tools/perf/ui/gtk/annotate.c                |  2 +-
 tools/perf/util/annotate.c                  | 27 +++++++++++++++--
 tools/perf/util/annotate.h                  |  4 ++-
 8 files changed, 136 insertions(+), 6 deletions(-)

-- 
2.7.4

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[PATCH v4 0/2] perf report: Implement visual marker for macro fusion in annotate Jin Yao <yao.jin@linux.intel.com> - 2017-07-07 07:10 +0200

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