GlobalISel: Move computeValueLLTs

Call lowering should use this directly instead of going through the
EVT version, but more work is needed to deal with this (mostly the
passing of the IR type pointer instead of the relevant properties in
ArgInfo).

llvm-svn: 358111

1 files changed, 30 insertions, 0 deletions

diff --git a/llvm/lib/CodeGen/Analysis.cpp b/llvm/lib/CodeGen/Analysis.cpp
index 9e3ab24..02f099f 100644
--- a/llvm/lib/CodeGen/Analysis.cpp
+++ b/llvm/lib/CodeGen/Analysis.cpp
@@ -113,6 +113,36 @@ void llvm::ComputeValueVTs(const TargetLowering &TLI, const DataLayout &DL,
     Offsets->push_back(StartingOffset);
 }
 
+void llvm::computeValueLLTs(const DataLayout &DL, Type &Ty,
+                            SmallVectorImpl<LLT> &ValueTys,
+                            SmallVectorImpl<uint64_t> *Offsets,
+                            uint64_t StartingOffset) {
+  // Given a struct type, recursively traverse the elements.
+  if (StructType *STy = dyn_cast<StructType>(&Ty)) {
+    const StructLayout *SL = DL.getStructLayout(STy);
+    for (unsigned I = 0, E = STy->getNumElements(); I != E; ++I)
+      computeValueLLTs(DL, *STy->getElementType(I), ValueTys, Offsets,
+                       StartingOffset + SL->getElementOffset(I));
+    return;
+  }
+  // Given an array type, recursively traverse the elements.
+  if (ArrayType *ATy = dyn_cast<ArrayType>(&Ty)) {
+    Type *EltTy = ATy->getElementType();
+    uint64_t EltSize = DL.getTypeAllocSize(EltTy);
+    for (unsigned i = 0, e = ATy->getNumElements(); i != e; ++i)
+      computeValueLLTs(DL, *EltTy, ValueTys, Offsets,
+                       StartingOffset + i * EltSize);
+    return;
+  }
+  // Interpret void as zero return values.
+  if (Ty.isVoidTy())
+    return;
+  // Base case: we can get an LLT for this LLVM IR type.
+  ValueTys.push_back(getLLTForType(Ty, DL));
+  if (Offsets != nullptr)
+    Offsets->push_back(StartingOffset * 8);
+}
+
 /// ExtractTypeInfo - Returns the type info, possibly bitcast, encoded in V.
 GlobalValue *llvm::ExtractTypeInfo(Value *V) {
   V = V->stripPointerCasts();