Reverse ordering of base and derived pointer during safepoint lowering.

According to the documentation in StackMap section for the safepoint we should have:
"The first Location in each pair describes the base pointer for the object. The second is the derived pointer actually being relocated."
But before this change we emitted them in reverse order - derived pointer first, base pointer second.

llvm-svn: 237126

1 files changed, 12 insertions, 10 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/StatepointLowering.cpp b/llvm/lib/CodeGen/SelectionDAG/StatepointLowering.cpp
index 6c40053cb46..4a21ce247c9 100644
--- a/llvm/lib/CodeGen/SelectionDAG/StatepointLowering.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/StatepointLowering.cpp
@@ -473,11 +473,12 @@ static void lowerStatepointMetaArgs(SmallVectorImpl<SDValue> &Ops,
     SDValue Incoming = Builder.getValue(V);
     reservePreviousStackSlotForValue(Incoming, Builder);
   }
-  for (unsigned i = 0; i < Bases.size() * 2; ++i) {
-    // Even elements will contain base, odd elements - derived ptr
-    const Value *V = i % 2 ? Bases[i / 2] : Ptrs[i / 2];
-    SDValue Incoming = Builder.getValue(V);
-    reservePreviousStackSlotForValue(Incoming, Builder);
+  for (unsigned i = 0; i < Bases.size(); ++i) {
+    const Value *Base = Bases[i];
+    reservePreviousStackSlotForValue(Builder.getValue(Base), Builder);
+
+    const Value *Ptr = Ptrs[i];
+    reservePreviousStackSlotForValue(Builder.getValue(Ptr), Builder);
   }
 
   // First, prefix the list with the number of unique values to be
@@ -512,11 +513,12 @@ static void lowerStatepointMetaArgs(SmallVectorImpl<SDValue> &Ops,
   // arrays interwoven with each (lowered) base pointer immediately followed by
   // it's (lowered) derived pointer.  i.e
   // (base[0], ptr[0], base[1], ptr[1], ...)
-  for (unsigned i = 0; i < Bases.size() * 2; ++i) {
-    // Even elements will contain base, odd elements - derived ptr
-    const Value *V = i % 2 ? Bases[i / 2] : Ptrs[i / 2];
-    SDValue Incoming = Builder.getValue(V);
-    lowerIncomingStatepointValue(Incoming, Ops, Builder);
+  for (unsigned i = 0; i < Bases.size(); ++i) {
+    const Value *Base = Bases[i];
+    lowerIncomingStatepointValue(Builder.getValue(Base), Ops, Builder);
+
+    const Value *Ptr = Ptrs[i];
+    lowerIncomingStatepointValue(Builder.getValue(Ptr), Ops, Builder);
   }
 
   // If there are any explicit spill slots passed to the statepoint, record