[v2,1/1] scripts/performance: Add dissect.py script

diff --git a/scripts/performance/dissect.py b/scripts/performance/dissect.py
new file mode 100755
index 0000000000..8c2967d082
--- /dev/null
+++ b/scripts/performance/dissect.py
@@ -0,0 +1,165 @@ 
+#!/usr/bin/env python3
+
+#  Print the percentage of instructions spent in each phase of QEMU
+#  execution.
+#
+#  Syntax:
+#  dissect.py [-h] -- <qemu executable> [<qemu executable options>] \
+#                   <target executable> [<target executable options>]
+#
+#  [-h] - Print the script arguments help message.
+#
+#  Example of usage:
+#  dissect.py -- qemu-arm coulomb_double-arm
+#
+#  This file is a part of the project "TCG Continuous Benchmarking".
+#
+#  Copyright (C) 2020  Ahmed Karaman <ahmedkhaledkaraman@gmail.com>
+#  Copyright (C) 2020  Aleksandar Markovic <aleksandar.qemu.devel@gmail.com>
+#
+#  This program is free software: you can redistribute it and/or modify
+#  it under the terms of the GNU General Public License as published by
+#  the Free Software Foundation, either version 2 of the License, or
+#  (at your option) any later version.
+#
+#  This program is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+#  GNU General Public License for more details.
+#
+#  You should have received a copy of the GNU General Public License
+#  along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+import argparse
+import os
+import subprocess
+import sys
+
+
+def get_JIT_line(callgrind_data):
+    """
+    Search for the first instance of the JIT call in
+    the callgrind_annotate output when ran using --tree=caller
+    This is equivalent to the self number of instructions of JIT.
+
+    Parameters:
+    callgrind_data (list): callgrind_annotate output
+
+    Returns:
+    (int): Line number
+   """
+    line = -1
+    for i in range(len(callgrind_data)):
+        if callgrind_data[i].strip('\n') and \
+                callgrind_data[i].split()[-1] == "[???]":
+            line = i
+            break
+    if line == -1:
+        sys.exit("Couldn't locate the JIT call ... Exiting.")
+    return line
+
+
+def main():
+    # Parse the command line arguments
+    parser = argparse.ArgumentParser(
+        usage='dissect.py [-h] -- '
+        '<qemu executable> [<qemu executable options>] '
+        '<target executable> [<target executable options>]')
+
+    parser.add_argument('command', type=str, nargs='+', help=argparse.SUPPRESS)
+
+    args = parser.parse_args()
+
+    # Extract the needed variables from the args
+    command = args.command
+
+    # Insure that valgrind is installed
+    check_valgrind = subprocess.run(
+        ["which", "valgrind"], stdout=subprocess.DEVNULL)
+    if check_valgrind.returncode:
+        sys.exit("Please install valgrind before running the script.")
+
+    # Run callgrind
+    callgrind = subprocess.run((["valgrind",
+                                 "--tool=callgrind",
+                                 "--callgrind-out-file=/tmp/callgrind.data"]
+                                + command),
+                               stdout=subprocess.DEVNULL,
+                               stderr=subprocess.PIPE)
+    if callgrind.returncode:
+        sys.exit(callgrind.stderr.decode("utf-8"))
+
+    # Save callgrind_annotate output to /tmp/callgrind_annotate.out
+    with open("/tmp/callgrind_annotate.out", "w") as output:
+        callgrind_annotate = subprocess.run(
+            ["callgrind_annotate", "/tmp/callgrind.data", "--tree=caller"],
+            stdout=output,
+            stderr=subprocess.PIPE)
+        if callgrind_annotate.returncode:
+            os.unlink('/tmp/callgrind.data')
+            output.close()
+            os.unlink('/tmp/callgrind_annotate.out')
+            sys.exit(callgrind_annotate.stderr.decode("utf-8"))
+
+    # Read the callgrind_annotate output to callgrind_data[]
+    callgrind_data = []
+    with open('/tmp/callgrind_annotate.out', 'r') as data:
+        callgrind_data = data.readlines()
+
+    # Line number with the total number of instructions
+    total_instructions_line_number = 20
+    # Get the total number of instructions
+    total_instructions_line_data = \
+        callgrind_data[total_instructions_line_number]
+    total_instructions = total_instructions_line_data.split()[0]
+    total_instructions = int(total_instructions.replace(',', ''))
+
+    # Line number with the JIT self number of instructions
+    JIT_self_instructions_line_number = get_JIT_line(callgrind_data)
+    # Get the JIT self number of instructions
+    JIT_self_instructions_line_data = \
+        callgrind_data[JIT_self_instructions_line_number]
+    JIT_self_instructions = JIT_self_instructions_line_data.split()[0]
+    JIT_self_instructions = int(JIT_self_instructions.replace(',', ''))
+
+    # Line number with the JIT self + inclusive number of instructions
+    # It's the line above the first JIT call when running with --tree=caller
+    JIT_total_instructions_line_number = JIT_self_instructions_line_number - 1
+    # Get the JIT self + inclusive number of instructions
+    JIT_total_instructions_line_data = \
+        callgrind_data[JIT_total_instructions_line_number]
+    JIT_total_instructions = JIT_total_instructions_line_data.split()[0]
+    JIT_total_instructions = int(JIT_total_instructions.replace(',', ''))
+
+    # Calculate number of instructions in helpers and code generation
+    helpers_instructions = JIT_total_instructions - JIT_self_instructions
+    code_generation_instructions = total_instructions - JIT_total_instructions
+
+    # Print results (Insert commas in large numbers)
+    # Print total number of instructions
+    print('{:<20}{:>20}\n'.
+          format("Total Instructions:",
+                 format(total_instructions, ',')))
+    # Print code generation instructions and percentage
+    print('{:<20}{:>20}\t{:>6.3f}%'.
+          format("Code Generation:",
+                 format(code_generation_instructions, ","),
+                 (code_generation_instructions / total_instructions) * 100))
+    # Print JIT instructions and percentage
+    print('{:<20}{:>20}\t{:>6.3f}%'.
+          format("JIT Execution:",
+                 format(JIT_self_instructions, ","),
+                 (JIT_self_instructions / total_instructions) * 100))
+    # Print helpers instructions and percentage
+    print('{:<20}{:>20}\t{:>6.3f}%'.
+          format("Helpers:",
+                 format(helpers_instructions, ","),
+                 (helpers_instructions/total_instructions)*100))
+
+    # Remove intermediate files
+    os.unlink('/tmp/callgrind.data')
+    os.unlink('/tmp/callgrind_annotate.out')
+
+
+if __name__ == "__main__":
+    main()