scons: Add a tag for arm fastmodel and use it.

This avoids some python logic in the SConscript files, and explicit
references to the configuration system.

Change-Id: If6ee61bb8c23606859e60323b8ca2c5254dbdecc
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/58356
Maintainer: Gabe Black <gabe.black@gmail.com>
Reviewed-by: Yu-hsin Wang <yuhsingw@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>

src/arch/arm/fastmodel/CortexA76/SConscript

@@ -25,9 +25,6 @@
 
 Import('*')
 
-if not env['CONF']['USE_ARM_FASTMODEL']:
-    Return()
-
 protocol_dir = Dir('..').Dir('protocol')
 
 for name in ('x1', 'x2', 'x3', 'x4'):
@@ -39,7 +36,8 @@ for name in ('x1', 'x2', 'x3', 'x4'):
 
 SimObject('FastModelCortexA76.py', sim_objects=[
     'FastModelCortexA76', 'FastModelCortexA76Cluster'] +
-    [f'FastModelScxEvsCortexA76x{num}' for num in (1, 2, 3, 4)])
-Source('cortex_a76.cc')
-Source('evs.cc')
-Source('thread_context.cc')
+    [f'FastModelScxEvsCortexA76x{num}' for num in (1, 2, 3, 4)],
+    tags='arm fastmodel')
+Source('cortex_a76.cc', tags='arm fastmodel')
+Source('evs.cc', tags='arm fastmodel')
+Source('thread_context.cc', tags='arm fastmodel')

src/arch/arm/fastmodel/CortexR52/SConscript

@@ -25,9 +25,6 @@
 
 Import('*')
 
-if not env['CONF']['USE_ARM_FASTMODEL']:
-    Return()
-
 protocol_dir = Dir('..').Dir('protocol')
 
 for name in ('x1', 'x2', 'x3', 'x4'):
@@ -40,7 +37,8 @@ for name in ('x1', 'x2', 'x3', 'x4'):
 
 SimObject('FastModelCortexR52.py', sim_objects=[
     'FastModelCortexR52', 'FastModelCortexR52Cluster'] +
-    [f'FastModelScxEvsCortexR52x{num}' for num in (1, 2, 3, 4)])
-Source('cortex_r52.cc')
-Source('evs.cc')
-Source('thread_context.cc')
+    [f'FastModelScxEvsCortexR52x{num}' for num in (1, 2, 3, 4)],
+    tags='arm fastmodel')
+Source('cortex_r52.cc', tags='arm fastmodel')
+Source('evs.cc', tags='arm fastmodel')
+Source('thread_context.cc', tags='arm fastmodel')

src/arch/arm/fastmodel/GIC/SConscript

@@ -25,13 +25,11 @@
 
 Import('*')
 
-if not env['CONF']['USE_ARM_FASTMODEL']:
-    Return()
-
 protocol_dir = Dir('..').Dir('protocol')
 
 ArmFastModelComponent(File('GIC.sgproj'), File('GIC.lisa'),
                       protocol_dir.File('SignalInterruptProtocol.lisa')
                       ).prepare_env(env)
-SimObject('FastModelGIC.py', sim_objects=['SCFastModelGIC', 'FastModelGIC'])
-Source('gic.cc')
+SimObject('FastModelGIC.py', sim_objects=['SCFastModelGIC', 'FastModelGIC'],
+        tags='arm fastmodel')
+Source('gic.cc', tags='arm fastmodel')

src/arch/arm/fastmodel/PL330_DMAC/SConscript

@@ -25,13 +25,11 @@
 
 Import('*')
 
-if not env['CONF']['USE_ARM_FASTMODEL']:
-    Return()
-
 protocol_dir = Dir('..').Dir('protocol')
 
 ArmFastModelComponent(File('PL330.sgproj'), File('PL330.lisa'),
                       protocol_dir.File('SignalInterruptProtocol.lisa')
                       ).prepare_env(env)
-SimObject('FastModelPL330.py', sim_objects=['FastModelPL330'])
-Source('pl330.cc')
+SimObject('FastModelPL330.py', sim_objects=['FastModelPL330'],
+        tags='arm fastmodel')
+Source('pl330.cc', tags='arm fastmodel')

src/arch/arm/fastmodel/SConscript

@@ -48,13 +48,11 @@ from gem5_scons import Transform, warning, error
 import os.path
 
 if env['CONF']['USE_ARM_FASTMODEL']:
-    if not env['CONF']['USE_SYSTEMC']:
+    if env['CONF']['USE_SYSTEMC']:
+        env.TagImplies('arm fastmodel', 'arm isa')
+    else:
         warning('ARM Fast Models require systemc support')
         env['CONF']['USE_ARM_FASTMODEL'] = False
-        Return()
-
-if not env['CONF']['USE_ARM_FASTMODEL']:
-    Return()
 
 
 systemc_home = Dir('#/src/systemc/ext/systemc_home')
@@ -144,11 +142,11 @@ fm_static_libs = (
     'IrisSupport',
 )
 for lib in fm_static_libs:
-    SourceLib(staticify(env, lib))
+    SourceLib(staticify(env, lib), tags='arm fastmodel')
 
-SourceLib('atomic')
-SourceLib('dl')
-SourceLib('rt')
+SourceLib('atomic', tags='arm fastmodel')
+SourceLib('dl', tags='arm fastmodel')
+SourceLib('rt', tags='arm fastmodel')
 
 class ProjectFileParser(Grammar):
     def __init__(self):
@@ -399,7 +397,9 @@ class ArmFastModelComponent(object):
         env.Append(LIBPATH=self.libpaths)
         env.AddLocalRPATH(*self.rpaths)
         env.Append(CPPPATH=self.headerpaths)
-        env.Prepend(LIBS=self.libs)
+        # Put these libraries earlier in the list by setting priority.
+        for lib in self.libs:
+            SourceLib(lib, priority=1, tags='arm fastmodel')
 
     def simgen_builder(self, target, source, env):
         cmd = self.simgen_cmd
@@ -414,10 +414,10 @@ class ArmFastModelComponent(object):
 
 Export('ArmFastModelComponent')
 
-PySource('m5', 'arm_fast_model.py')
-Source('fastmodel.cc')
+PySource('m5', 'arm_fast_model.py', tags='arm fastmodel')
+Source('fastmodel.cc', tags='arm fastmodel')
 
 SimObject('FastModel.py', sim_objects=[
-    'AmbaToTlmBridge64', 'AmbaFromTlmBridge64'])
-Source('amba_to_tlm_bridge.cc')
-Source('amba_from_tlm_bridge.cc')
+    'AmbaToTlmBridge64', 'AmbaFromTlmBridge64'], tags='arm fastmodel')
+Source('amba_to_tlm_bridge.cc', tags='arm fastmodel')
+Source('amba_from_tlm_bridge.cc', tags='arm fastmodel')

src/arch/arm/fastmodel/iris/SConscript

@@ -25,14 +25,12 @@
 
 Import('*')
 
-if not env['CONF']['USE_ARM_FASTMODEL']:
-    Return()
-
 SimObject('Iris.py', sim_objects=[
-    'IrisTLB', 'IrisMMU', 'IrisInterrupts', 'IrisISA', 'IrisBaseCPU'])
-Source('cpu.cc')
-Source('interrupts.cc')
-Source('isa.cc')
-Source('tlb.cc')
+    'IrisTLB', 'IrisMMU', 'IrisInterrupts', 'IrisISA', 'IrisBaseCPU'],
+    tags='arm fastmodel')
+Source('cpu.cc', tags='arm fastmodel')
+Source('interrupts.cc', tags='arm fastmodel')
+Source('isa.cc', tags='arm fastmodel')
+Source('tlb.cc', tags='arm fastmodel')
 
-Source('thread_context.cc')
+Source('thread_context.cc', tags='arm fastmodel')

src/arch/arm/fastmodel/reset_controller/SConscript

@@ -25,10 +25,7 @@
 
 Import('*')
 
-if not env['CONF']['USE_ARM_FASTMODEL']:
-    Return()
-
 SimObject('FastModelResetControllerExample.py', sim_objects=[
-    'FastModelResetControllerExample'])
+    'FastModelResetControllerExample'], tags='arm fastmodel')
 
-Source('example.cc')
+Source('example.cc', tags='arm fastmodel')