From 1d90e530442477de247dcb613f5176fe7e9beded Mon Sep 17 00:00:00 2001
From: Simon Pilgrim <llvm-dev@redking.me.uk>
Date: Mon, 19 Oct 2020 14:05:29 +0100
Subject: [PATCH] [InstCombine] foldOrOfICmps - pull out repeated getOperand()
 calls. NFCI.

---
 .../Transforms/InstCombine/InstCombineAndOrXor.cpp | 33 +++++++++-------------
 1 file changed, 13 insertions(+), 20 deletions(-)

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp b/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
index 11cfa4a..8fa2111 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
@@ -2281,9 +2281,10 @@ Value *InstCombinerImpl::foldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS,
     return V;
 
   ICmpInst::Predicate PredL = LHS->getPredicate(), PredR = RHS->getPredicate();
-
-  ConstantInt *LHSC = dyn_cast<ConstantInt>(LHS->getOperand(1));
-  ConstantInt *RHSC = dyn_cast<ConstantInt>(RHS->getOperand(1));
+  Value *LHS0 = LHS->getOperand(0), *RHS0 = RHS->getOperand(0);
+  Value *LHS1 = LHS->getOperand(1), *RHS1 = RHS->getOperand(1);
+  auto *LHSC = dyn_cast<ConstantInt>(LHS1);
+  auto *RHSC = dyn_cast<ConstantInt>(RHS1);
 
   // Fold (icmp ult/ule (A + C1), C3) | (icmp ult/ule (A + C2), C3)
   //                   -->  (icmp ult/ule ((A & ~(C1 ^ C2)) + max(C1, C2)), C3)
@@ -2295,19 +2296,15 @@ Value *InstCombinerImpl::foldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS,
   // 3) C1 ^ C2 is one-bit mask.
   // 4) LowRange1 ^ LowRange2 and HighRange1 ^ HighRange2 are one-bit mask.
   // This implies all values in the two ranges differ by exactly one bit.
-
   if ((PredL == ICmpInst::ICMP_ULT || PredL == ICmpInst::ICMP_ULE) &&
       PredL == PredR && LHSC && RHSC && LHS->hasOneUse() && RHS->hasOneUse() &&
       LHSC->getType() == RHSC->getType() &&
       LHSC->getValue() == (RHSC->getValue())) {
 
-    Value *LAdd = LHS->getOperand(0);
-    Value *RAdd = RHS->getOperand(0);
-
     Value *LAddOpnd, *RAddOpnd;
     ConstantInt *LAddC, *RAddC;
-    if (match(LAdd, m_Add(m_Value(LAddOpnd), m_ConstantInt(LAddC))) &&
-        match(RAdd, m_Add(m_Value(RAddOpnd), m_ConstantInt(RAddC))) &&
+    if (match(LHS0, m_Add(m_Value(LAddOpnd), m_ConstantInt(LAddC))) &&
+        match(RHS0, m_Add(m_Value(RAddOpnd), m_ConstantInt(RAddC))) &&
         LAddC->getValue().ugt(LHSC->getValue()) &&
         RAddC->getValue().ugt(LHSC->getValue())) {
 
@@ -2342,15 +2339,12 @@ Value *InstCombinerImpl::foldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS,
 
   // (icmp1 A, B) | (icmp2 A, B) --> (icmp3 A, B)
   if (predicatesFoldable(PredL, PredR)) {
-    if (LHS->getOperand(0) == RHS->getOperand(1) &&
-        LHS->getOperand(1) == RHS->getOperand(0))
+    if (LHS0 == RHS1 && LHS1 == RHS0)
       LHS->swapOperands();
-    if (LHS->getOperand(0) == RHS->getOperand(0) &&
-        LHS->getOperand(1) == RHS->getOperand(1)) {
-      Value *Op0 = LHS->getOperand(0), *Op1 = LHS->getOperand(1);
+    if (LHS0 == RHS0 && LHS1 == RHS1) {
       unsigned Code = getICmpCode(LHS) | getICmpCode(RHS);
       bool IsSigned = LHS->isSigned() || RHS->isSigned();
-      return getNewICmpValue(Code, IsSigned, Op0, Op1, Builder);
+      return getNewICmpValue(Code, IsSigned, LHS0, LHS1, Builder);
     }
   }
 
@@ -2359,26 +2353,25 @@ Value *InstCombinerImpl::foldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS,
   if (Value *V = foldLogOpOfMaskedICmps(LHS, RHS, false, Builder))
     return V;
 
-  Value *LHS0 = LHS->getOperand(0), *RHS0 = RHS->getOperand(0);
   if (LHS->hasOneUse() || RHS->hasOneUse()) {
     // (icmp eq B, 0) | (icmp ult A, B) -> (icmp ule A, B-1)
     // (icmp eq B, 0) | (icmp ugt B, A) -> (icmp ule A, B-1)
     Value *A = nullptr, *B = nullptr;
     if (PredL == ICmpInst::ICMP_EQ && LHSC && LHSC->isZero()) {
       B = LHS0;
-      if (PredR == ICmpInst::ICMP_ULT && LHS0 == RHS->getOperand(1))
+      if (PredR == ICmpInst::ICMP_ULT && LHS0 == RHS1)
         A = RHS0;
       else if (PredR == ICmpInst::ICMP_UGT && LHS0 == RHS0)
-        A = RHS->getOperand(1);
+        A = RHS1;
     }
     // (icmp ult A, B) | (icmp eq B, 0) -> (icmp ule A, B-1)
     // (icmp ugt B, A) | (icmp eq B, 0) -> (icmp ule A, B-1)
     else if (PredR == ICmpInst::ICMP_EQ && RHSC && RHSC->isZero()) {
       B = RHS0;
-      if (PredL == ICmpInst::ICMP_ULT && RHS0 == LHS->getOperand(1))
+      if (PredL == ICmpInst::ICMP_ULT && RHS0 == LHS1)
         A = LHS0;
       else if (PredL == ICmpInst::ICMP_UGT && LHS0 == RHS0)
-        A = LHS->getOperand(1);
+        A = LHS1;
     }
     if (A && B)
       return Builder.CreateICmp(
-- 
2.7.4