From 0bc76fc58223dd672416ca956b56bcc8905675a2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ciro=20Santilli=20=E5=85=AD=E5=9B=9B=E4=BA=8B=E4=BB=B6=20?=
 =?UTF-8?q?=E6=B3=95=E8=BD=AE=E5=8A=9F?= <ciro.santilli@gmail.com>
Date: Wed, 22 Jan 2020 00:00:00 +0000
Subject: [PATCH] gem5: bring fast build back to life and benchmark it on busy
 loop

---
 README.adoc | 56 ++++++++++++++++++++++++++++++++++++++++-------------
 common.py   |  5 ++++-
 2 files changed, 47 insertions(+), 14 deletions(-)

diff --git a/README.adoc b/README.adoc
index 277d324..968b544 100644
--- a/README.adoc
+++ b/README.adoc
@@ -12155,6 +12155,18 @@ In order to use different build options, you might also want to use <<gem5-build
 
 Explained at: xref:debug-the-emulator[xrefstyle=full].
 
+==== gem5 fast build
+
+....
+./build-gem5 --gem5-build-type fast
+....
+
+How it goes faster is explained at: https://stackoverflow.com/questions/59860091/how-to-increase-the-simulation-speed-of-a-gem5-run/59861375#59861375
+
+Benchmarks present at:
+
+* xref:benchmark-emulators-on-userland-executables[xrefstyle=full]
+
 ==== gem5 clang build
 
 TODO test properly, benchmark vs GCC.
@@ -19747,7 +19759,7 @@ Summary of manually collected results on <<p51>> at LKMC a18f28e263c91362519ef55
 |QEMU busy loop
 |a18f28e263c91362519ef550150b5c9d75fa3679 + 1
 |link:userland/gcc/busy_loop.c[] `-O0`
-|`qemu --arch aarch64 --userland userland/gcc/busy_loop.c `
+|`./run --arch aarch64 --userland userland/gcc/busy_loop.c `
 |10^10
 |68
 |1.1 * 10^11 (approx)
@@ -19756,25 +19768,43 @@ Summary of manually collected results on <<p51>> at LKMC a18f28e263c91362519ef55
 |gem5 busy loop
 |a18f28e263c91362519ef550150b5c9d75fa3679 + 1
 |link:userland/gcc/busy_loop.c[] `-O0`
-|`gem5 --arch aarch64 --userland userland/gcc/busy_loop.c`
-|10^7
-|100
-|1.10018162 * 10^8
-|1
+|`./run --arch aarch64 --emulator gem5 --static --userland userland/gcc/busy_loop.c --userland-args 1000000`
+|10^6
+|18
+|2.4005699 * 10^7
+|1.3
 
 |gem5 busy loop for a debug build
 |a18f28e263c91362519ef550150b5c9d75fa3679 + 1
 |link:userland/gcc/busy_loop.c[] `-O0`
-|`gem5 --arch aarch64 --gem5-build-id debug --userland userland/gcc/busy_loop.c --userland-args 100000`
+|`./run --arch aarch64 --emulator gem5 --gem5-build-type debug --static --userland userland/gcc/busy_loop.c --userland-args 100000`
 |10^5
-|32
-|2.528728 * 10^6
-|0.08
+|33
+|2.405682 * 10^6
+|0.07
+
+|gem5 busy loop for a fast build
+|0d5a41a3f88fcd7ed40fc19474fe5aed0463663f + 1
+|link:userland/gcc/busy_loop.c[] `-O0 -static`
+|`./run --arch aarch64 --emulator gem5 --gem5-build-type fast --static --userland userland/gcc/busy_loop.c --userland-args 1000000`
+|10^6
+|15
+|2.4005699 * 10^7
+|1.6
+
+|gem5 busy loop for a <<gem5-cpu-types,TimingSimpleCPU>>
+|a18f28e263c91362519ef550150b5c9d75fa3679 + 1
+|link:userland/gcc/busy_loop.c[] `-O0`
+|`+./run --arch aarch64 --emulator gem5 --arch aarch64 --static --userland userland/gcc/busy_loop.c --userland-args 1000000 -- --cpu-type TimingSimpleCPU --caches+`
+|10^6
+|26
+|2.4005699 * 10^7
+|0.9
 
 |gem5 busy loop for a <<gem5-cpu-types,MinorCPU>>
 |a18f28e263c91362519ef550150b5c9d75fa3679 + 1
 |link:userland/gcc/busy_loop.c[] `-O0`
-|`+gem5 --arch aarch64 --userland userland/gcc/busy_loop.c --userland-args 1000000 -- --cpu-type MinorCPU --caches+`
+|`+./run --arch aarch64 --emulator gem5 --arch aarch64 --userland userland/gcc/busy_loop.c --userland-args 1000000 -- --cpu-type MinorCPU --caches+`
 |10^6
 |31
 |1.1018152 * 10^7
@@ -19783,7 +19813,7 @@ Summary of manually collected results on <<p51>> at LKMC a18f28e263c91362519ef55
 |gem5 busy loop for a <<gem5-cpu-types,DerivO3CPU>>
 |a18f28e263c91362519ef550150b5c9d75fa3679 + 1
 |link:userland/gcc/busy_loop.c[] `-O0`
-|`+gem5 --arch aarch64 --userland userland/gcc/busy_loop.c --userland args 1000000 -- --cpu-type DerivO3CPU --caches+`
+|`+./run --arch aarch64 --emulator gem5 --userland userland/gcc/busy_loop.c --userland args 1000000 -- --cpu-type DerivO3CPU --caches+`
 |10^6
 |52
 |1.1018128 * 10^7
@@ -19792,7 +19822,7 @@ Summary of manually collected results on <<p51>> at LKMC a18f28e263c91362519ef55
 |
 |a18f28e263c91362519ef550150b5c9d75fa3679 + 1
 |link:userland/gcc/busy_loop.c[] `-O0`
-|`+gem5 --arch aarch64 --gem5-build-id MOESI_CMP_directory -- --cpu-type DerivO3CPU --caches --ruby+`
+|`+./run --arch aarch64 --emulator gem5 --gem5-build-id MOESI_CMP_directory -- --cpu-type DerivO3CPU --caches --ruby+`
 |1 * 1000000 = 10^6
 |63
 |1.1005150 * 10^7
diff --git a/common.py b/common.py
index 9b60b4d..359f377 100644
--- a/common.py
+++ b/common.py
@@ -150,6 +150,9 @@ consts['build_type_choices'] = [
     # -O0 -g
     'debug'
 ]
+consts['gem5_build_type_choices'] = consts['build_type_choices'] + [
+    'fast',
+]
 consts['build_type_default'] = 'opt'
 # Files whose basename start with this are gitignored.
 consts['tmp_prefix'] = 'tmp.'
@@ -333,7 +336,7 @@ Default: {}
         )
         self.add_argument(
             '--gem5-build-type',
-            choices=consts['build_type_choices'],
+            choices=consts['gem5_build_type_choices'],
             default=consts['build_type_default'],
             help='gem5 build type, most often used for "debug" builds.'
         )