R600/SI: Use VSrc_* register classes as the default classes for types

Since the VSrc_* register classes contain both VGPRs and SGPRs, copies
that used be emitted by isel like this:

SGPR = COPY VGPR

Will now be emitted like this:

VSrC = COPY VGPR

This patch also adds a pass that tries to identify and fix situations where
a VGPR to SGPR copy may occur.  Hopefully, these changes will make it
impossible for the compiler to generate illegal VGPR to SGPR copies.

llvm-svn: 187831

1 files changed, 2 insertions, 0 deletions

diff --git a/llvm/lib/Target/R600/AMDGPUTargetMachine.cpp b/llvm/lib/Target/R600/AMDGPUTargetMachine.cpp
index 1a304962e11..5ebc5f27dc4 100644
--- a/llvm/lib/Target/R600/AMDGPUTargetMachine.cpp
+++ b/llvm/lib/Target/R600/AMDGPUTargetMachine.cpp
@@ -146,6 +146,8 @@ bool AMDGPUPassConfig::addPreRegAlloc() {
 
   if (ST.getGeneration() <= AMDGPUSubtarget::NORTHERN_ISLANDS) {
     addPass(createR600VectorRegMerger(*TM));
+  } else {
+    addPass(createSIFixSGPRCopiesPass(*TM));
   }
   return false;
 }