Code for 64bit emulation of uint64 to float conversion uses

splitBasicBlock() which invalidates current insert point. The
fix is to set the correct insert point after the method call
completes.

Change-Id: Id4a85268b8393a78d99d2467c622da123254421e

Author: mmerecki

IGC/Compiler/CISACodeGen/Emu64OpsPass.cpp

@@ -1381,6 +1381,13 @@ bool InstExpander::visitFPToSI(FPToSIInst &F2S) {
   return true;
 }
 
+// Note: This method uses splitBasciBlock() which moves Pos (and all
+// instructions following it till the end of basic block) to a new basic block.
+// If IRB's insert point is set to Pos or an instruction after Pos in the same
+// basic block than the insert basic block value in IRB will be invalid after
+// this method completes. A correct insert point should be set in IRB after this
+// method is called.
+// 
 Value *InstExpander::convertUIToFP32(Type *DstTy, Value *Lo, Value *Hi, Instruction *Pos) {
   BuilderType::InsertPointGuard Guard(*IRB);
   IRB->SetInsertPoint(Pos);
@@ -1499,6 +1506,7 @@ bool InstExpander::visitUIToFP(UIToFPInst &U2F) {
     NewVal = IRB->CreateCall3(Fma, HiF, FC0, LoF);
   } else {
     NewVal = convertUIToFP32(IRB->getFloatTy(), Lo, Hi, &U2F);
+    IRB->SetInsertPoint(&U2F);
     // It's OK to apply the same approach in `convertUIToFP32` to convert 64-bit
     // integer into half. But, it would introduce a little more instructions to
     // properly round the remaining 48 bits into the high 16 bits. Instead, that
@@ -1558,6 +1566,7 @@ bool InstExpander::visitSIToFP(SIToFPInst &S2F) {
     Hi = IRB->CreateExtractValue(V, 1);
 
     NewVal = convertUIToFP32(IRB->getFloatTy(), Lo, Hi, &S2F);
+    IRB->SetInsertPoint(&S2F);
     NewVal = IRB->CreateBitCast(NewVal, IRB->getInt32Ty());
     Sign = IRB->CreateAnd(Sign, IRB->getInt32(0x80000000));
     NewVal = IRB->CreateOr(NewVal, Sign);