From 7a5052b3a0e1bfb54f3f1c3dd3eba633526829b0 Mon Sep 17 00:00:00 2001
From: Hoa Nguyen <hn@hnpl.org>
Date: Sun, 3 Dec 2023 13:22:11 -0800
Subject: [PATCH] arch-arm: Only build ArmCapstoneDisassembler when ISA is arm
 (#553)

Currently, if the Capstone header file is found in the host system,
scons will try to build the ArmCapstoneDisassembler regardless of the
gem5 target ISA. This is causing problem when the host has Capstone, but
the gem5 target ISA is not arm. Compiling gem5 in this case will cause
errors, e.g., ArmISA and ArmSystem is not found.

This change aims to prevent building the ArmCapstoneDisassembler when
the gem5 target ISA is not arm.

Ref:
[1] The Arm Capstone PR https://github.com/gem5/gem5/pull/494

Change-Id: I1e714d34aec8fe2a2af8cd351536951053a4d8a5
---
 src/arch/arm/tracers/SConscript | 6 +++---
 src/cpu/Kconfig                 | 6 ++++++
 src/cpu/SConscript              | 8 +++++---
 3 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/src/arch/arm/tracers/SConscript b/src/arch/arm/tracers/SConscript
index ca012c5c2e..7b729ad065 100644
--- a/src/arch/arm/tracers/SConscript
+++ b/src/arch/arm/tracers/SConscript
@@ -43,7 +43,7 @@ Source('tarmac_tracer.cc', tags='arm isa')
 Source('tarmac_record.cc', tags='arm isa')
 Source('tarmac_record_v8.cc', tags='arm isa')
 
-if env['CONF']['HAVE_CAPSTONE']:
+if env['CONF']['USE_CAPSTONE']:
     SimObject('ArmCapstone.py', sim_objects=['ArmCapstoneDisassembler'],
-              tags=['capstone', 'arm isa'])
-    Source('capstone.cc', tags=['capstone', 'arm isa'])
+              tags=['arm isa'])
+    Source('capstone.cc', tags=['arm isa'])
diff --git a/src/cpu/Kconfig b/src/cpu/Kconfig
index 33a00e9c45..e1f96678c8 100644
--- a/src/cpu/Kconfig
+++ b/src/cpu/Kconfig
@@ -27,3 +27,9 @@ config HAVE_CAPSTONE
     def_bool $(HAVE_CAPSTONE)
 
 rsource "kvm/Kconfig"
+
+config USE_CAPSTONE
+    depends on HAVE_CAPSTONE
+    depends on USE_ARM_ISA
+    bool "Use CapstoneDisassembler"
+    default y
diff --git a/src/cpu/SConscript b/src/cpu/SConscript
index 03ba7b924d..64c64903bd 100644
--- a/src/cpu/SConscript
+++ b/src/cpu/SConscript
@@ -115,9 +115,11 @@ Source('simple_thread.cc')
 Source('thread_context.cc')
 Source('thread_state.cc')
 Source('timing_expr.cc')
-SourceLib('capstone', tags='capstone')
-Source('capstone.cc', tags='capstone')
-SimObject('Capstone.py', sim_objects=['CapstoneDisassembler'], tags='capstone')
+
+if env['CONF']['USE_CAPSTONE']:
+    SourceLib('capstone')
+    Source('capstone.cc')
+    SimObject('Capstone.py', sim_objects=['CapstoneDisassembler'])
 
 SimObject('DummyChecker.py', sim_objects=['DummyChecker'])
 Source('checker/cpu.cc')