[llvm] r352067 - [SelectionDAGBuilder] Simplify HasSideEffect calculation. NFC.

[Nirav Dave via llvm-commits]

Author: niravd
Date: Thu Jan 24 09:56:03 2019
New Revision: 352067

URL: http://llvm.org/viewvc/llvm-project?rev=352067&view=rev
Log:
[SelectionDAGBuilder] Simplify HasSideEffect calculation. NFC.

Modified:
    llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp?rev=352067&r1=352066&r2=352067&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp Thu Jan 24 09:56:03 2019
@@ -7505,9 +7505,9 @@ void SelectionDAGBuilder::visitInlineAsm
   TargetLowering::AsmOperandInfoVector TargetConstraints = TLI.ParseConstraints(
       DAG.getDataLayout(), DAG.getSubtarget().getRegisterInfo(), CS);
 
-  bool hasMemory = false;
-
-  // Remember the HasSideEffect, AlignStack, AsmDialect, MayLoad and MayStore
+  // First Pass: Calculate HasSideEffects and ExtraFlags (AlignStack,
+  // AsmDialect, MayLoad, MayStore).
+  bool HasSideEffect = IA->hasSideEffects();
   ExtraFlags ExtraInfo(CS);
 
   unsigned ArgNo = 0;   // ArgNo - The argument of the CallInst.
@@ -7550,8 +7550,8 @@ void SelectionDAGBuilder::visitInlineAsm
       OpInfo.ConstraintVT = MVT::Other;
     }
 
-    if (!hasMemory)
-      hasMemory = OpInfo.hasMemory(TLI);
+    if (!HasSideEffect)
+      HasSideEffect = OpInfo.hasMemory(TLI);
 
     // Determine if this InlineAsm MayLoad or MayStore based on the constraints.
     // FIXME: Could we compute this on OpInfo rather than T?
@@ -7562,14 +7562,9 @@ void SelectionDAGBuilder::visitInlineAsm
     ExtraInfo.update(T);
   }
 
-  SDValue Chain, Flag;
-
   // We won't need to flush pending loads if this asm doesn't touch
   // memory and is nonvolatile.
-  if (hasMemory || IA->hasSideEffects())
-    Chain = getRoot();
-  else
-    Chain = DAG.getRoot();
+  SDValue Flag, Chain = (HasSideEffect) ? getRoot() : DAG.getRoot();
 
   // Second pass over the constraints: compute which constraint option to use.
   for (SDISelAsmOperandInfo &OpInfo : ConstraintOperands) {
@@ -7925,8 +7920,7 @@ void SelectionDAGBuilder::visitInlineAsm
     Chain = DAG.getNode(ISD::TokenFactor, getCurSDLoc(), MVT::Other, OutChains);
 
   // Only Update Root if inline assembly has a memory effect.
-  if (ResultValues.empty() || IA->hasSideEffects() || hasMemory ||
-      !OutChains.empty())
+  if (ResultValues.empty() || HasSideEffect || !OutChains.empty())
     DAG.setRoot(Chain);
 }