d574381081
The SmartDict, used by buildEnv, has been added long time ago for
the following reasons: (checking its documentation)
---
The SmartDict class fixes a couple of issues with using the content
of os.environ or similar dicts of strings as Python variables:
1) Undefined variables should return False rather than raising KeyError.
2) String values of 'False', '0', etc., should evaluate to False
(not just the empty string).
---
These are valid reasons, but I believe they should be addressed in
a more standardized way by using a common dictionary.
1) We should simply rely on dict.get
if buildEnv.get('KEY', False/None):
2) We should discourage the use of stringified False or 0.
If we are using a dictionary, can't we just pass those values as
booleans?
The SmartDict is basically converting every value into a
string ("Variable") at every access (__getitem__)
The Variable is a string + some "basic" conversion methods
What is the problem of passing every dict value as a string?
The problem is the ambiguity on the boolean conversion.
If a variable is modelling a boolean, we can return true if
the value is 'yes', 'true'... and false if the value is
'no', 'false' etc. We should raise an exception if it is
something different, like a typo (e.g.) 'Fasle'.
But if the variable is not modelling a boolean, we don't know
how to handle that. How should we convert 'mystring' ?
If we decide to treat 'mystring' as True (which is basically
what a str.__bool__ would return) we will break typoes detection,
as 'Fasle' will now be converted to True, rather than raising
an exception.
Change-Id: I960fbfb1ec0f703e1e372dd752ee75f00632acac
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/37775
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Reviewed-by: Hoa Nguyen <hoanguyen@ucdavis.edu>
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Maintainer: Gabe Black <gabe.black@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
This is the gem5 simulator. The main website can be found at http://www.gem5.org A good starting point is http://www.gem5.org/about, and for more information about building the simulator and getting started please see http://www.gem5.org/documentation and http://www.gem5.org/documentation/learning_gem5/introduction. To build gem5, you will need the following software: g++ or clang, Python (gem5 links in the Python interpreter), SCons, SWIG, zlib, m4, and lastly protobuf if you want trace capture and playback support. Please see http://www.gem5.org/documentation/general_docs/building for more details concerning the minimum versions of the aforementioned tools. Once you have all dependencies resolved, type 'scons build/<ARCH>/gem5.opt' where ARCH is one of ARM, NULL, MIPS, POWER, SPARC, or X86. This will build an optimized version of the gem5 binary (gem5.opt) for the the specified architecture. See http://www.gem5.org/documentation/general_docs/building for more details and options. The basic source release includes these subdirectories: - configs: example simulation configuration scripts - ext: less-common external packages needed to build gem5 - src: source code of the gem5 simulator - system: source for some optional system software for simulated systems - tests: regression tests - util: useful utility programs and files To run full-system simulations, you will need compiled system firmware (console and PALcode for Alpha), kernel binaries and one or more disk images. If you have questions, please send mail to gem5-users@gem5.org Enjoy using gem5 and please share your modifications and extensions.