Remove the simplify-libcalls pass (finally)

This commit completely removes what is left of the simplify-libcalls
pass.  All of the functionality has now been migrated to the instcombine
and functionattrs passes.  The following C API functions are now NOPs:

  1. LLVMAddSimplifyLibCallsPass
  2. LLVMPassManagerBuilderSetDisableSimplifyLibCalls

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184459 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/IPO/PassManagerBuilder.cpp b/lib/Transforms/IPO/PassManagerBuilder.cpp
index 20aad6f..9d88608 100644
--- a/lib/Transforms/IPO/PassManagerBuilder.cpp
+++ b/lib/Transforms/IPO/PassManagerBuilder.cpp
@@ -54,7 +54,6 @@
     SizeLevel = 0;
     LibraryInfo = 0;
     Inliner = 0;
-    DisableSimplifyLibCalls = false;
     DisableUnitAtATime = false;
     DisableUnrollLoops = false;
     BBVectorize = RunBBVectorization;
@@ -174,8 +173,6 @@
   else
     MPM.add(createScalarReplAggregatesPass(-1, false));
   MPM.add(createEarlyCSEPass());              // Catch trivial redundancies
-  if (!DisableSimplifyLibCalls)
-    MPM.add(createSimplifyLibCallsPass());    // Library Call Optimizations
   MPM.add(createJumpThreadingPass());         // Thread jumps.
   MPM.add(createCorrelatedValuePropagationPass()); // Propagate conditionals
   MPM.add(createCFGSimplificationPass());     // Merge & remove BBs
@@ -379,8 +376,7 @@
 void
 LLVMPassManagerBuilderSetDisableSimplifyLibCalls(LLVMPassManagerBuilderRef PMB,
                                                  LLVMBool Value) {
-  PassManagerBuilder *Builder = unwrap(PMB);
-  Builder->DisableSimplifyLibCalls = Value;
+  // NOTE: The simplify-libcalls pass has been removed.
 }
 
 void