[AMDGPU] Allow finer grain control of an unaligned access speed

A target can return if a misaligned access is 'fast' as defined
by the target or not. In reality there can be different levels
of 'fast' and 'slow'. This patch changes the boolean 'Fast'
argument of the allowsMisalignedMemoryAccesses family of functions
to an unsigned representing its speed.

A target can still define it as it wants and the direct translation
of the current code uses 0 and 1 for current false and true. This
makes the change an NFC.

Subsequent patch will start using an actual value of speed in
the load/store vectorizer to compare if a vectorized access going
to be not just fast, but not slower than before.

Differential Revision: https://reviews.llvm.org/D124217

1 files changed, 6 insertions, 6 deletions

diff --git a/llvm/lib/CodeGen/TargetLoweringBase.cpp b/llvm/lib/CodeGen/TargetLoweringBase.cpp
index 9736318..03325b2 100644
--- a/llvm/lib/CodeGen/TargetLoweringBase.cpp
+++ b/llvm/lib/CodeGen/TargetLoweringBase.cpp
@@ -1716,7 +1716,7 @@ uint64_t TargetLoweringBase::getByValTypeAlignment(Type *Ty,
 
 bool TargetLoweringBase::allowsMemoryAccessForAlignment(
     LLVMContext &Context, const DataLayout &DL, EVT VT, unsigned AddrSpace,
-    Align Alignment, MachineMemOperand::Flags Flags, bool *Fast) const {
+    Align Alignment, MachineMemOperand::Flags Flags, unsigned *Fast) const {
   // Check if the specified alignment is sufficient based on the data layout.
   // TODO: While using the data layout works in practice, a better solution
   // would be to implement this check directly (make this a virtual function).
@@ -1726,7 +1726,7 @@ bool TargetLoweringBase::allowsMemoryAccessForAlignment(
   if (VT.isZeroSized() || Alignment >= DL.getABITypeAlign(Ty)) {
     // Assume that an access that meets the ABI-specified alignment is fast.
     if (Fast != nullptr)
-      *Fast = true;
+      *Fast = 1;
     return true;
   }
 
@@ -1736,7 +1736,7 @@ bool TargetLoweringBase::allowsMemoryAccessForAlignment(
 
 bool TargetLoweringBase::allowsMemoryAccessForAlignment(
     LLVMContext &Context, const DataLayout &DL, EVT VT,
-    const MachineMemOperand &MMO, bool *Fast) const {
+    const MachineMemOperand &MMO, unsigned *Fast) const {
   return allowsMemoryAccessForAlignment(Context, DL, VT, MMO.getAddrSpace(),
                                         MMO.getAlign(), MMO.getFlags(), Fast);
 }
@@ -1745,7 +1745,7 @@ bool TargetLoweringBase::allowsMemoryAccess(LLVMContext &Context,
                                             const DataLayout &DL, EVT VT,
                                             unsigned AddrSpace, Align Alignment,
                                             MachineMemOperand::Flags Flags,
-                                            bool *Fast) const {
+                                            unsigned *Fast) const {
   return allowsMemoryAccessForAlignment(Context, DL, VT, AddrSpace, Alignment,
                                         Flags, Fast);
 }
@@ -1753,7 +1753,7 @@ bool TargetLoweringBase::allowsMemoryAccess(LLVMContext &Context,
 bool TargetLoweringBase::allowsMemoryAccess(LLVMContext &Context,
                                             const DataLayout &DL, EVT VT,
                                             const MachineMemOperand &MMO,
-                                            bool *Fast) const {
+                                            unsigned *Fast) const {
   return allowsMemoryAccess(Context, DL, VT, MMO.getAddrSpace(), MMO.getAlign(),
                             MMO.getFlags(), Fast);
 }
@@ -1761,7 +1761,7 @@ bool TargetLoweringBase::allowsMemoryAccess(LLVMContext &Context,
 bool TargetLoweringBase::allowsMemoryAccess(LLVMContext &Context,
                                             const DataLayout &DL, LLT Ty,
                                             const MachineMemOperand &MMO,
-                                            bool *Fast) const {
+                                            unsigned *Fast) const {
   EVT VT = getApproximateEVTForLLT(Ty, DL, Context);
   return allowsMemoryAccess(Context, DL, VT, MMO.getAddrSpace(), MMO.getAlign(),
                             MMO.getFlags(), Fast);