Replace push_back(Constructor(foo)) with emplace_back(foo) for non-trivial types
If the type isn't trivially moveable emplace can skip a potentially
expensive move. It also saves a couple of characters.
Call sites were found with the ASTMatcher + some semi-automated cleanup.
memberCallExpr(
argumentCountIs(1), callee(methodDecl(hasName("push_back"))),
on(hasType(recordDecl(has(namedDecl(hasName("emplace_back")))))),
hasArgument(0, bindTemporaryExpr(
hasType(recordDecl(hasNonTrivialDestructor())),
has(constructExpr()))),
unless(isInTemplateInstantiation()))
No functional change intended.
llvm-svn: 238602
diff --git a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
index be49cd1..9d602c6 100644
--- a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
@@ -1843,7 +1843,7 @@
case Instruction::BitCast:
case Instruction::GetElementPtr:
- Users.push_back(I);
+ Users.emplace_back(I);
Worklist.push_back(I);
continue;
@@ -1852,7 +1852,7 @@
// We can fold eq/ne comparisons with null to false/true, respectively.
if (!ICI->isEquality() || !isa<ConstantPointerNull>(ICI->getOperand(1)))
return false;
- Users.push_back(I);
+ Users.emplace_back(I);
continue;
}
@@ -1878,13 +1878,13 @@
case Intrinsic::lifetime_start:
case Intrinsic::lifetime_end:
case Intrinsic::objectsize:
- Users.push_back(I);
+ Users.emplace_back(I);
continue;
}
}
if (isFreeCall(I, TLI)) {
- Users.push_back(I);
+ Users.emplace_back(I);
continue;
}
return false;
@@ -1893,7 +1893,7 @@
StoreInst *SI = cast<StoreInst>(I);
if (SI->isVolatile() || SI->getPointerOperand() != PI)
return false;
- Users.push_back(I);
+ Users.emplace_back(I);
continue;
}
}