Subzero: ARM32: lowering of vector insert and extract.

src/IceTargetLoweringARM32.h

Index: src/IceTargetLoweringARM32.h
diff --git a/src/IceTargetLoweringARM32.h b/src/IceTargetLoweringARM32.h
index af55141c9ca34ff6be36b379707fcc59f83bf929..9d24b9f91f73c23bcc2f47f11af722ef597f1388 100644
--- a/src/IceTargetLoweringARM32.h
+++ b/src/IceTargetLoweringARM32.h
@@ -85,13 +85,19 @@ public:
   const llvm::SmallBitVector &
   getRegistersForVariable(const Variable *Var) const override {
     RegClass RC = Var->getRegClass();
-    assert(RC < RC_Target);
-    return TypeToRegisterSet[RC];
+    switch (RC) {
+    default:
+      assert(RC < RC_Target);
+      return TypeToRegisterSet[RC];
+    case RegARM32::RCARM32_QtoS:
+      assert(RegARM32::RCARM32_QtoS < RegARM32::RCARM32_NUM);

[Jim Stichnoth, 2016/02/03 15:28:38]

I think this assert is pretty much guaranteed to be true and you can remove it. 
(Another possibility is to use static_assert, but it's trivially true enough
that I just wouldn't bother.)

[Eric Holk, 2016/02/03 21:02:22]

Done.

+      return TypeToRegisterSet[RC];
+    }
   }
   const llvm::SmallBitVector &
   getAllRegistersForVariable(const Variable *Var) const override {
     RegClass RC = Var->getRegClass();
-    assert(RC < RC_Target);
+    assert((RegARM32::RegClassARM32)RC < RegARM32::RCARM32_NUM);
     return TypeToRegisterSetUnfiltered[RC];
   }
   const llvm::SmallBitVector &getAliasesForRegister(SizeT Reg) const override {
@@ -413,6 +419,20 @@ protected:
     }
   }
 
+  // Generates a vmov instruction to extract the given index from a vector
+  // register.
+  void _extract(Variable *Dest, Variable *Src, uint32_t Index,

[Jim Stichnoth, 2016/02/03 15:28:38]

I would probably rename Src to Src0 for consistency.

[John, 2016/02/03 16:06:52]

It's been common practice (at least in the ARM32 backend) to name something Src
if it is the only Src. Unfortunately, this is not always followed, but I think
it makes moar sense -- if I see Src0 in the middle of a function I am tempted to
think there might be a Src1.

regardless of parameter naming, I would name this method _extract_element (and
_insert_element) simply because _insert and _extract are too generic.

[Eric Holk, 2016/02/03 21:02:22]

Done.

[Eric Holk, 2016/02/03 21:02:22]

Done.

+                CondARM32::Cond Pred = CondARM32::AL) {
+    Context.insert<InstARM32Extract>(Dest, Src, Index, Pred);
+  }
+
+  // Generates a vmov instruction to insert a value into the given index of a
+  // vector register.
+  void _insert(Variable *Dest, Variable *Val, uint32_t Index,

[Jim Stichnoth, 2016/02/03 15:28:38]

I would probably rename Val to Src0 for consistency.

[Eric Holk, 2016/02/03 21:02:22]

Done.

+               CondARM32::Cond Pred = CondARM32::AL) {
+    Context.insert<InstARM32Insert>(Dest, Val, Index, Pred);
+  }
+
   // --------------------------------------------------------------------------
   // Begin bool folding machinery.
   //