Avoid copies of std::strings and APInt/APFloats where we only read from it

As suggested by clang-tidy's performance-unnecessary-copy-initialization.
This can easily hit lifetime issues, so I audited every change and ran the
tests under asan, which came back clean.

llvm-svn: 272126

3 files changed, 9 insertions, 9 deletions

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
index 49bc662d129..e124dbdc1a9 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
@@ -1866,7 +1866,7 @@ Instruction *InstCombiner::visitCallInst(CallInst &CI) {
 
     // Attempt to simplify to a constant, shuffle vector or INSERTQI call.
     if (CI11) {
-      APInt V11 = CI11->getValue();
+      const APInt &V11 = CI11->getValue();
       APInt Len = V11.zextOrTrunc(6);
       APInt Idx = V11.lshr(8).zextOrTrunc(6);
       if (Value *V = simplifyX86insertq(*II, Op0, Op1, Len, Idx, *Builder))
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
index b3727e4bbe5..bfd73f4bbac 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
@@ -1444,8 +1444,8 @@ Instruction *InstCombiner::FoldICmpCstShrCst(ICmpInst &I, Value *Op, Value *A,
     return new ICmpInst(Pred, LHS, RHS);
   };
 
-  APInt AP1 = CI1->getValue();
-  APInt AP2 = CI2->getValue();
+  const APInt &AP1 = CI1->getValue();
+  const APInt &AP2 = CI2->getValue();
 
   // Don't bother doing any work for cases which InstSimplify handles.
   if (AP2 == 0)
@@ -1508,8 +1508,8 @@ Instruction *InstCombiner::FoldICmpCstShlCst(ICmpInst &I, Value *Op, Value *A,
     return new ICmpInst(Pred, LHS, RHS);
   };
 
-  APInt AP1 = CI1->getValue();
-  APInt AP2 = CI2->getValue();
+  const APInt &AP1 = CI1->getValue();
+  const APInt &AP2 = CI2->getValue();
 
   // Don't bother doing any work for cases which InstSimplify handles.
   if (AP2 == 0)
@@ -2092,8 +2092,8 @@ Instruction *InstCombiner::visitICmpInstWithInstAndIntCst(ICmpInst &ICI,
   case Instruction::UDiv:
     if (ConstantInt *DivLHS = dyn_cast<ConstantInt>(LHSI->getOperand(0))) {
       Value *X = LHSI->getOperand(1);
-      APInt C1 = RHS->getValue();
-      APInt C2 = DivLHS->getValue();
+      const APInt &C1 = RHS->getValue();
+      const APInt &C2 = DivLHS->getValue();
       assert(C2 != 0 && "udiv 0, X should have been simplified already.");
       // (icmp ugt (udiv C2, X), C1) -> (icmp ule X, C2/(C1+1))
       if (ICI.getPredicate() == ICmpInst::ICMP_UGT) {
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp b/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
index ecf94dc70a7..69773a57ecb 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
@@ -663,8 +663,8 @@ Instruction *InstCombiner::FoldSPFofSPF(Instruction *Inner,
   if (SPF1 == SPF2) {
     if (ConstantInt *CB = dyn_cast<ConstantInt>(B)) {
       if (ConstantInt *CC = dyn_cast<ConstantInt>(C)) {
-        APInt ACB = CB->getValue();
-        APInt ACC = CC->getValue();
+        const APInt &ACB = CB->getValue();
+        const APInt &ACC = CC->getValue();
 
         // MIN(MIN(A, 23), 97) -> MIN(A, 23)
         // MAX(MAX(A, 97), 23) -> MAX(A, 97)