Make DataLayout Non-Optional in the Module

Summary:
DataLayout keeps the string used for its creation.

As a side effect it is no longer needed in the Module.
This is "almost" NFC, the string is no longer
canonicalized, you can't rely on two "equals" DataLayout
having the same string returned by getStringRepresentation().

Get rid of DataLayoutPass: the DataLayout is in the Module

The DataLayout is "per-module", let's enforce this by not
duplicating it more than necessary.
One more step toward non-optionality of the DataLayout in the
module.

Make DataLayout Non-Optional in the Module

Module->getDataLayout() will never returns nullptr anymore.

Reviewers: echristo

Subscribers: resistor, llvm-commits, jholewinski

Differential Revision: http://reviews.llvm.org/D7992

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 231270
diff --git a/llvm/lib/Transforms/IPO/Inliner.cpp b/llvm/lib/Transforms/IPO/Inliner.cpp
index 305ad7a..fe12612 100644
--- a/llvm/lib/Transforms/IPO/Inliner.cpp
+++ b/llvm/lib/Transforms/IPO/Inliner.cpp
@@ -121,8 +121,7 @@
 /// any new allocas to the set if not possible.
 static bool InlineCallIfPossible(CallSite CS, InlineFunctionInfo &IFI,
                                  InlinedArrayAllocasTy &InlinedArrayAllocas,
-                                 int InlineHistory, bool InsertLifetime,
-                                 const DataLayout *DL) {
+                                 int InlineHistory, bool InsertLifetime) {
   Function *Callee = CS.getCalledFunction();
   Function *Caller = CS.getCaller();
 
@@ -198,11 +197,6 @@
 
       unsigned Align1 = AI->getAlignment(),
                Align2 = AvailableAlloca->getAlignment();
-      // If we don't have data layout information, and only one alloca is using
-      // the target default, then we can't safely merge them because we can't
-      // pick the greater alignment.
-      if (!DL && (!Align1 || !Align2) && Align1 != Align2)
-        continue;
       
       // The available alloca has to be in the right function, not in some other
       // function in this SCC.
@@ -223,8 +217,8 @@
 
       if (Align1 != Align2) {
         if (!Align1 || !Align2) {
-          assert(DL && "DataLayout required to compare default alignments");
-          unsigned TypeAlign = DL->getABITypeAlignment(AI->getAllocatedType());
+          const DataLayout &DL = Caller->getParent()->getDataLayout();
+          unsigned TypeAlign = DL.getABITypeAlignment(AI->getAllocatedType());
 
           Align1 = Align1 ? Align1 : TypeAlign;
           Align2 = Align2 ? Align2 : TypeAlign;
@@ -432,8 +426,6 @@
 bool Inliner::runOnSCC(CallGraphSCC &SCC) {
   CallGraph &CG = getAnalysis<CallGraphWrapperPass>().getCallGraph();
   AssumptionCacheTracker *ACT = &getAnalysis<AssumptionCacheTracker>();
-  DataLayoutPass *DLP = getAnalysisIfAvailable<DataLayoutPass>();
-  const DataLayout *DL = DLP ? &DLP->getDataLayout() : nullptr;
   auto *TLIP = getAnalysisIfAvailable<TargetLibraryInfoWrapperPass>();
   const TargetLibraryInfo *TLI = TLIP ? &TLIP->getTLI() : nullptr;
   AliasAnalysis *AA = &getAnalysis<AliasAnalysis>();
@@ -495,7 +487,7 @@
 
   
   InlinedArrayAllocasTy InlinedArrayAllocas;
-  InlineFunctionInfo InlineInfo(&CG, DL, AA, ACT);
+  InlineFunctionInfo InlineInfo(&CG, AA, ACT);
 
   // Now that we have all of the call sites, loop over them and inline them if
   // it looks profitable to do so.
@@ -553,7 +545,7 @@
 
         // Attempt to inline the function.
         if (!InlineCallIfPossible(CS, InlineInfo, InlinedArrayAllocas,
-                                  InlineHistoryID, InsertLifetime, DL)) {
+                                  InlineHistoryID, InsertLifetime)) {
           emitOptimizationRemarkMissed(CallerCtx, DEBUG_TYPE, *Caller, DLoc,
                                        Twine(Callee->getName() +
                                              " will not be inlined into " +