Before this patch, I don't think it was possible to change (say)
CFLAGS as part of running the make command. Nor did setting them when
running configure do anything. Getting this right is a little fiddly:
for example, see Automake's approach at [1] ("AM_CFLAGS" and friends).
This patch adds an "mcppbs-" prefix, and sets things up properly for
CFLAGS, CPPFLAGS, CXXFLAGS and LDFLAGS. Note that the bulk of the
patch is either the auto-generated configure script or the ax_*.m4
files vendored in from the autoconf archive (needed to handle
--export-dynamic correctly without trashing settings from the user
running configure).
What's supposed to happen is as follows:
- Base compilation flags that should apply to everything (standard
optimisation flags, warning flags etc.) are defined in
Makefile.in.
- When the user runs configure, they can set compilation flags on
the command line. These end up as environment variables in the
shell script.
- Compilation flags that can only be decided when we run
configure (this is currently just whether we support
-Wl,--export-dynamic) are appended to the configure-time LDFLAGS
environment variable.
- At the end of the configure script, these environment variables
are spliced into Makefile.in to fill out the corresponding
@<varname>@ entries.
- When running make, the user might again override compilation
flags. These will get appended to the flags found so far.
As a concrete example:
mkdir build
cd build
../configure CXXFLAGS='-O3'
make CXXFLAGS='-O0'
will result in c++ compile commands that look like this:
g++ -MMD -MP \
-DPREFIX=\"/usr/local\" -Wall -Wno-unused -g -O2 -std=c++11 \
-O3 \
-O0 \
-I. -I.. -I../fesvr -I../riscv -I../dummy_rocc -I../softfloat \
-I../spike_main -fPIC -c ../fesvr/elfloader.cc
(I've added some newlines to wrap the long line).
Note that we have the base flags from Makefile.in (called
$(default-CXXFLAGS) there) first. Then we have the -O3 from the
configure command. Finally we have the -O0 from the Make command line.
And I can finally run "make CXXFLAGS='-O0 -g3'". Phew!
[1] https://www.gnu.org/software/automake/manual/html_node/Flag-Variables-Ordering.html
1. configure option "--with-varch"
the option defines the default u-arch implementatiton-decided parameter
VLEN: vector register length in bit
SLEN: striping distance in bit
ELEN: max element size in bit
ex: --with-vector=v128:e32:s128
2. add __int128_t type checking
3. add --varch command option and help message
ex: --varch=v512:e64:s512
Signed-off-by: Dave Wen <dave.wen@sifive.com>
The actual Spike package consists of a whole bunch of libraries. This
installs a pkg-config file for each generated library, and a meta
pkg-config file (riscv-spike.pc) that links in all the other Spike
libraries except dummy_rocc (which I figure isn't interesting).
This allows me to package and install spike, and then use that package
to build an extension library (so I don't have to fork Spike for my
own ISA extension).
Moved cross-compiler to /xcc/ rather than /
Added ISA sim in /sim/
Added Proxy Kernel in /pk/ (to be cleaned up)
Added opcode map to /opcodes/ (ditto)
Added documentation to /doc/