Fix typos encountered while working on pass pipeline for O1.

llvm/lib/Passes/PassBuilder.cpp

@@ -857,7 +857,7 @@ ModulePassManager PassBuilder::buildModuleSimplificationPipeline(
   // constants.
   MPM.addPass(createModuleToFunctionPassAdaptor(PromotePass()));
 
-  // Remove any dead arguments exposed by cleanups and constand folding
+  // Remove any dead arguments exposed by cleanups and constant folding
   // globals.
   MPM.addPass(DeadArgumentEliminationPass());
 

llvm/lib/Transforms/Scalar/LowerConstantIntrinsics.cpp

@@ -145,7 +145,7 @@ namespace {
 /// Legacy pass for lowering is.constant intrinsics out of the IR.
 ///
 /// When this pass is run over a function it converts is.constant intrinsics
-/// into 'true' or 'false'. This is completements the normal constand folding
+/// into 'true' or 'false'. This complements the normal constant folding
 /// to 'true' as part of Instruction Simplify passes.
 class LowerConstantIntrinsics : public FunctionPass {
 public:

llvm/test/CodeGen/X86/2010-01-11-ExtraPHIArg.ll

@@ -1,6 +1,6 @@
 ; RUN: llc -verify-machineinstrs < %s
 ;
-; The lowering of a switch combined with constand folding would leave spurious extra arguments on a PHI instruction.
+; The lowering of a switch combined with constant folding would leave spurious extra arguments on a PHI instruction.
 ;
 target triple = "x86_64-apple-darwin10"