Portable dev (#105)

* Force portable code

* Switch to old MMX instructions, avoiding SSE & SSE2 instructions.

* Less agressive, leave verus code (which checks for it) using advanced instructions.

* Compiling only for windows

* Update .gitlab-ci.yml

* Try -march=native for C++ code generation.

* Tweaking machine architecture settings.

* Try native alone.

* Also get LIBCRYPTOCONDITIONS to -march=native

* Switch other lib to native as well.

* Try switching back further for CPU architecture.

* Even lower end settings.

* Turn on symbols.

* Use sse2,3 and 4 capable x64.

* Once again let verus lib use advances instructioins since it checjs via CPUID at run time.

* Modify a few more makefile entries.

* Switch to AMD model similar to our test system.

* Get snark makefile to k8 too.

* Yet another -march to modify to k8, or two of them.

* Brute force k8 settings, comment non-portable code out.

* Put the condition on cpuid back.

* Put non-portable advenced instruction code back

* Enable instructions.

* Add lib for separate settings.

* Update .gitlab-ci.yml

* Update .gitlab-ci.yml

* Update .gitlab-ci.yml

* Update .gitlab-ci.yml

* replacing k8-sse3 specific flags to x86-84

* updating versions

src/snark/Makefile

@@ -15,7 +15,7 @@ endif
 
 # To override these, use "make OPTFLAGS=..." etc.
 CURVE = BN128
-OPTFLAGS = -O2 -march=native -mtune=native
+OPTFLAGS = -O2 -march=x86-64 -g -mtune=x86-64
 FEATUREFLAGS = -DUSE_ASM -DMONTGOMERY_OUTPUT
 
 # Initialize this using "CXXFLAGS=... make". The makefile appends to that.
@@ -158,7 +158,7 @@ ifeq ($(DEBUG),1)
 endif
 
 ifeq ($(PERFORMANCE),1)
-        OPTFLAGS = -O3 -march=native -mtune=native
+        OPTFLAGS = -O3 -march=x86-64 -g -mtune=x86-64
         CXXFLAGS += -DNDEBUG
         # Enable link-time optimization:
         CXXFLAGS += -flto -fuse-linker-plugin