AMDGPU: Allow vectorization of packed types

llvm-svn: 305844
diff --git a/llvm/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.cpp b/llvm/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.cpp
index 0d6689b..88245b0 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.cpp
+++ b/llvm/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.cpp
@@ -184,9 +184,9 @@
   }
 }
 
-unsigned AMDGPUTTIImpl::getNumberOfRegisters(bool Vec) {
-  if (Vec)
-    return 0;
+unsigned AMDGPUTTIImpl::getHardwareNumberOfRegisters(bool Vec) const {
+  // The concept of vector registers doesn't really exist. Some packed vector
+  // operations operate on the normal 32-bit registers.
 
   // Number of VGPRs on SI.
   if (ST->getGeneration() >= AMDGPUSubtarget::SOUTHERN_ISLANDS)
@@ -195,8 +195,18 @@
   return 4 * 128; // XXX - 4 channels. Should these count as vector instead?
 }
 
+unsigned AMDGPUTTIImpl::getNumberOfRegisters(bool Vec) const {
+  // This is really the number of registers to fill when vectorizing /
+  // interleaving loops, so we lie to avoid trying to use all registers.
+  return getHardwareNumberOfRegisters(Vec) >> 3;
+}
+
 unsigned AMDGPUTTIImpl::getRegisterBitWidth(bool Vector) const {
-  return Vector ? 0 : 32;
+  return 32;
+}
+
+unsigned AMDGPUTTIImpl::getMinVectorRegisterBitWidth() const {
+  return 32;
 }
 
 unsigned AMDGPUTTIImpl::getLoadStoreVecRegBitWidth(unsigned AddrSpace) const {
@@ -247,11 +257,11 @@
 
 unsigned AMDGPUTTIImpl::getMaxInterleaveFactor(unsigned VF) {
   // Disable unrolling if the loop is not vectorized.
+  // TODO: Enable this again.
   if (VF == 1)
     return 1;
 
-  // Semi-arbitrary large amount.
-  return 64;
+  return 8;
 }
 
 int AMDGPUTTIImpl::getArithmeticInstrCost(
diff --git a/llvm/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.h b/llvm/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.h
index a60b1bb..485e204 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.h
+++ b/llvm/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.h
@@ -75,8 +75,10 @@
     return TTI::PSK_FastHardware;
   }
 
-  unsigned getNumberOfRegisters(bool Vector);
-  unsigned getRegisterBitWidth(bool Vector) const;
+  unsigned getHardwareNumberOfRegisters(bool Vector) const;
+  unsigned getNumberOfRegisters(bool Vector) const;
+  unsigned getRegisterBitWidth(bool Vector) const ;
+  unsigned getMinVectorRegisterBitWidth() const;
   unsigned getLoadStoreVecRegBitWidth(unsigned AddrSpace) const;
 
   bool isLegalToVectorizeMemChain(unsigned ChainSizeInBytes,