- Update register allocation hint after coalescing. This is done by the target since the hint is target dependent. This is important for ARM register pair hints.

- Register allocator should resolve the second part of the hint (register number) before passing it to the target since it knows virtual register to physical register mapping.
- More fixes to get ARM load / store double word working.

llvm-svn: 73671

2 files changed, 11 insertions, 2 deletions

diff --git a/llvm/lib/CodeGen/RegAllocLinearScan.cpp b/llvm/lib/CodeGen/RegAllocLinearScan.cpp
index f7f5dc74b5d..41a42fd22d3 100644
--- a/llvm/lib/CodeGen/RegAllocLinearScan.cpp
+++ b/llvm/lib/CodeGen/RegAllocLinearScan.cpp
@@ -1356,9 +1356,15 @@ unsigned RALinScan::getFreePhysReg(LiveInterval* cur,
   unsigned FreeReg = 0;
   unsigned FreeRegInactiveCount = 0;
 
+  std::pair<unsigned, unsigned> Hint = mri_->getRegAllocationHint(cur->reg);
+  // Resolve second part of the hint (if possible) given the current allocation.
+  unsigned physReg = Hint.second;
+  if (physReg &&
+      TargetRegisterInfo::isVirtualRegister(physReg) && vrm_->hasPhys(physReg))
+    physReg = vrm_->getPhys(physReg);
+
   TargetRegisterClass::iterator I, E;
-  tie(I, E) = tri_->getAllocationOrder(RC,
-                                    mri_->getRegAllocationHint(cur->reg), *mf_);
+  tie(I, E) = tri_->getAllocationOrder(RC, Hint.first, physReg, *mf_);
   assert(I != E && "No allocatable register in this register class!");
 
   // Scan for the first available register.
diff --git a/llvm/lib/CodeGen/SimpleRegisterCoalescing.cpp b/llvm/lib/CodeGen/SimpleRegisterCoalescing.cpp
index c363ba52b5e..20348055bd9 100644
--- a/llvm/lib/CodeGen/SimpleRegisterCoalescing.cpp
+++ b/llvm/lib/CodeGen/SimpleRegisterCoalescing.cpp
@@ -1766,6 +1766,9 @@ bool SimpleRegisterCoalescing::JoinCopy(CopyRec &TheCopy, bool &Again) {
   // being merged.
   li_->removeInterval(SrcReg);
 
+  // Update regalloc hint.
+  tri_->UpdateRegAllocHint(SrcReg, DstReg, *mf_);
+
   // Manually deleted the live interval copy.
   if (SavedLI) {
     SavedLI->clear();