[llvm] 1398460 - [RISCVGatherScatterLowering] Minor code cleanup [NFC]

[Philip Reames via llvm-commits]

Author: Philip Reames
Date: 2023-05-12T10:33:29-07:00
New Revision: 13984608992246e42e66c019f09764650d60af63

URL: https://github.com/llvm/llvm-project/commit/13984608992246e42e66c019f09764650d60af63
DIFF: https://github.com/llvm/llvm-project/commit/13984608992246e42e66c019f09764650d60af63.diff

LOG: [RISCVGatherScatterLowering] Minor code cleanup [NFC]

Use a switch to avoid repeat tests on the opcode, and factor out some common code out of another switch.  (Not all branches had both common bits, but the one which didn't left the values unchanged and their starting value is the respective operand - so storing it back is a nop.)

Added: 
    

Modified: 
    llvm/lib/Target/RISCV/RISCVGatherScatterLowering.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Target/RISCV/RISCVGatherScatterLowering.cpp b/llvm/lib/Target/RISCV/RISCVGatherScatterLowering.cpp
index e844e1b11271..0174aa547a1b 100644
--- a/llvm/lib/Target/RISCV/RISCVGatherScatterLowering.cpp
+++ b/llvm/lib/Target/RISCV/RISCVGatherScatterLowering.cpp
@@ -225,20 +225,24 @@ bool RISCVGatherScatterLowering::matchStridedRecurrence(Value *Index, Loop *L,
   if (!BO)
     return false;
 
-  if (BO->getOpcode() != Instruction::Add &&
-      BO->getOpcode() != Instruction::Or &&
-      BO->getOpcode() != Instruction::Mul &&
-      BO->getOpcode() != Instruction::Shl)
-    return false;
-
-  // Only support shift by constant.
-  if (BO->getOpcode() == Instruction::Shl && !isa<Constant>(BO->getOperand(1)))
-    return false;
-
-  // We need to be able to treat Or as Add.
-  if (BO->getOpcode() == Instruction::Or &&
-      !haveNoCommonBitsSet(BO->getOperand(0), BO->getOperand(1), *DL))
+  switch (BO->getOpcode()) {
+  default:
     return false;
+  case Instruction::Or:
+    // We need to be able to treat Or as Add.
+    if (!haveNoCommonBitsSet(BO->getOperand(0), BO->getOperand(1), *DL))
+      return false;
+    break;
+  case Instruction::Add:
+    break;
+  case Instruction::Shl:
+    // Only support shift by constant.
+    if (!isa<Constant>(BO->getOperand(1)))
+      return false;
+    break;
+  case Instruction::Mul:
+    break;
+  }
 
   // We should have one operand in the loop and one splat.
   Value *OtherOp;
@@ -291,7 +295,6 @@ bool RISCVGatherScatterLowering::matchStridedRecurrence(Value *Index, Loop *L,
       Start = SplatOp;
     else
       Start = Builder.CreateAdd(Start, SplatOp, "start");
-    BasePtr->setIncomingValue(StartBlock, Start);
     break;
   }
   case Instruction::Mul: {
@@ -306,8 +309,6 @@ bool RISCVGatherScatterLowering::matchStridedRecurrence(Value *Index, Loop *L,
       Stride = SplatOp;
     else
       Stride = Builder.CreateMul(Stride, SplatOp, "stride");
-    Inc->setOperand(StepIndex, Step);
-    BasePtr->setIncomingValue(StartBlock, Start);
     break;
   }
   case Instruction::Shl: {
@@ -316,12 +317,12 @@ bool RISCVGatherScatterLowering::matchStridedRecurrence(Value *Index, Loop *L,
       Start = Builder.CreateShl(Start, SplatOp, "start");
     Step = Builder.CreateShl(Step, SplatOp, "step");
     Stride = Builder.CreateShl(Stride, SplatOp, "stride");
-    Inc->setOperand(StepIndex, Step);
-    BasePtr->setIncomingValue(StartBlock, Start);
     break;
   }
   }
 
+  Inc->setOperand(StepIndex, Step);
+  BasePtr->setIncomingValue(StartBlock, Start);
   return true;
 }