Linux compilation - some patches included

[Tub]

Hi,

Now and then I've been trying to get dolphin to run on linux. Today was the first time I got it both compiling and starting emulation without segfaulting!

Anyway, a couple of patches were needed.

r4108_linux_fixes.patch
Edit: not needed any more, those are fixed in latest trunk


so finally it worked! But when pressing "Stop" during a game, it segfaulted. Valgrind to the rescue! Well, or not.

The valgrind.log said:

Code:

vex amd64->IR: unhandled instruction bytes: 0x66 0xF 0x29 0xC6 0x66 0xF
==18815== valgrind: Unrecognised instruction at address 0x1872024e.

and I have no idea how to debug that. However, I fixed another valgrind warning:

r4108_gpfifo_memmove.patch

Code:

Index: Source/Core/Core/Src/HW/GPFifo.cpp
===================================================================
--- Source/Core/Core/Src/HW/GPFifo.cpp    (revision 4108)
+++ Source/Core/Core/Src/HW/GPFifo.cpp    (working copy)
@@ -77,7 +77,8 @@
        m_gatherPipeCount -= GATHER_PIPE_SIZE;
        
        // HyperIris: dunno why, but I use memcpy
-        memcpy(m_gatherPipe, m_gatherPipe + GATHER_PIPE_SIZE, m_gatherPipeCount);
+        // Tub: memcpy is not guaranteed to work if source and destination overlap, memmove is safe.
+        memmove(m_gatherPipe, m_gatherPipe + GATHER_PIPE_SIZE, m_gatherPipeCount);
        
        // increase the CPUWritePointer
        CPeripheralInterface::Fifo_CPUWritePointer += GATHER_PIPE_SIZE;

granted, memcpy() should work fine if your system uses the trivial implementation, but doing it the proper way doesn't hurt.


I'd be happy to see those patches commited to trunk by a dev

---

I thought it was a little slow, so I tried to compile it with Profile-guided Optimization.


r4108_enable_pgo.patch

Code:

Index: SConstruct
===================================================================
--- SConstruct    (revision 4108)
+++ SConstruct    (working copy)
@@ -120,6 +120,10 @@
                  ignorecase = 2
                  ),
     PathVariable('wxconfig', 'Path to the wxconfig', None),
+    EnumVariable('pgo', 'Profile-Guided Optimization (generate or use)', 'none',
+                allowed_values = ('none', 'generate', 'use'),
+                ignorecase = 2
+                ),
     ('CC', 'The c compiler', 'gcc'),
     ('CXX', 'The c++ compiler', 'g++'),
     )
@@ -193,6 +197,15 @@
elif (flavour == 'release'):
     compileFlags.append('-O3')

+# pgo - Profile Guided Optimization
+if env['pgo']=='generate':
+    compileFlags.append('-fprofile-generate')
+    env['LINKFLAGS']='-fprofile-generate'
+if env['pgo']=='use':
+    compileFlags.append('-fprofile-use')
+    env['LINKFLAGS']='-fprofile-use'
+
+
# more warnings
if env['lint']:
     warnings.append('error')

To create an optimized binary, do this:

1. scons flavor=release pgo=generate
2. run the binary, start a game, play a little. It'll run slower than usual, because it's busy generating the profile.
3. scons flavor=release pgo=use
4. run the new binary, which is now optimized!
   

some short tests suggest that PGO yields about ~3% more fps. Yay! \o/


again, feel free to commit this to trunk