Merge remote-tracking branch 'origin/GP-1270_DoublePrecisionInfLoop'

into patch (Fixes NationalSecurityAgency#3105)

Author: ryanmkurtz

Ghidra/Features/Decompiler/src/decompile/cpp/double.cc

@@ -723,6 +723,8 @@ void SplitVarnode::wholeList(Varnode *w,vector<SplitVarnode> &splitvec)
     }
   }
   if (res==0) return;
+  if (res == 3 && (basic.lo->getSize() + basic.hi->getSize() != basic.wholesize))
+    return;
 
   splitvec.push_back(basic);
   findCopies(basic,splitvec);

Ghidra/Features/Decompiler/src/decompile/cpp/ruleaction.cc

@@ -7610,6 +7610,8 @@ int4 RuleSplitFlow::applyOp(PcodeOp *op,Funcdata &data)
   Varnode *vn = op->getIn(0);
   if (!vn->isWritten())
     return 0;
+  if (vn->isPrecisLo() || vn->isPrecisHi())
+    return 0;
   if (op->getOut()->getSize() + loSize != vn->getSize())
     return 0;				// Make sure SUBPIECE is taking most significant part
   PcodeOp *concatOp = (PcodeOp *)0;

Ghidra/Features/Decompiler/src/decompile/cpp/subflow.cc

@@ -1554,6 +1554,8 @@ bool SplitFlow::traceForward(TransformVar *rvn)
       break;
     case CPUI_SUBPIECE:
     {
+      if (outvn->isPrecisLo() || outvn->isPrecisHi())
+	return false;		// Do not split if we know value comes from double precision pieces
       uintb val = op->getIn(1)->getOffset();
       if ((val==0)&&(outvn->getSize() == laneDescription.getSize(0))) {
 	TransformOp *rop = newPreexistingOp(1,CPUI_COPY,op);	// Grabs the low piece