Merge pull request #5372 from apple/revert-5265-wip-generics-inlining-flag

Revert "[sil-performance-inliner] Re-introduce inlining of generics as a staging feature behind a flag"

Author: DougGregor

lib/SILOptimizer/Transforms/PerformanceInliner.cpp

@@ -14,7 +14,6 @@
 #include "swift/SILOptimizer/PassManager/Passes.h"
 #include "swift/SILOptimizer/PassManager/Transforms.h"
 #include "swift/SILOptimizer/Utils/PerformanceInlinerUtils.h"
-#include "swift/Strings.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/CommandLine.h"
@@ -27,10 +26,6 @@ llvm::cl::opt<bool> PrintShortestPathInfo(
     "print-shortest-path-info", llvm::cl::init(false),
     llvm::cl::desc("Print shortest-path information for inlining"));
 
-llvm::cl::opt<bool> EnableSILInliningOfGenerics(
-    "sil-inline-generics", llvm::cl::init(false),
-    llvm::cl::desc("Enable inlining of generics"));
-
 //===----------------------------------------------------------------------===//
 //                           Performance Inliner
 //===----------------------------------------------------------------------===//
@@ -127,11 +122,6 @@ class SILPerformanceInliner {
                             ConstantTracker &constTracker,
                             int &NumCallerBlocks);
 
-  bool isProfitableToInlineGeneric(FullApplySite AI,
-                            Weight CallerWeight,
-                            ConstantTracker &constTracker,
-                            int &NumCallerBlocks);
-
   bool isProfitableInColdBlock(FullApplySite AI, SILFunction *Callee);
 
   void visitColdBlocks(SmallVectorImpl<FullApplySite> &AppliesToInline,
@@ -201,6 +191,10 @@ SILFunction *SILPerformanceInliner::getEligibleFunction(FullApplySite AI) {
     return nullptr;
   }
 
+  // We don't support this yet.
+  if (AI.hasSubstitutions())
+    return nullptr;
+
   SILFunction *Caller = AI.getFunction();
 
   // We don't support inlining a function that binds dynamic self because we
@@ -375,37 +369,6 @@ bool SILPerformanceInliner::isProfitableToInlineNonGeneric(FullApplySite AI,
   return true;
 }
 
-/// Return true if inlining this call site is profitable.
-bool SILPerformanceInliner::isProfitableToInlineGeneric(FullApplySite AI,
-                                              Weight CallerWeight,
-                                              ConstantTracker &callerTracker,
-                                              int &NumCallerBlocks) {
-  assert(!AI.getSubstitutions().empty() &&
-         "Expected a generic apply");
-
-  SILFunction *Callee = AI.getReferencedFunction();
-
-  // Do not inline @_semantics functions when compiling the stdlib,
-  // because they need to be preserved, so that the optimizer
-  // can properly optimize a user code later.
-  auto ModuleName = Callee->getModule().getSwiftModule()->getName().str();
-  if (Callee->hasSemanticsAttrThatStartsWith("array.") &&
-      (ModuleName == STDLIB_NAME || ModuleName == SWIFT_ONONE_SUPPORT))
-    return false;
-
-  // Always inline generic functions which are marked as
-  // AlwaysInline or transparent.
-  bool ShouldInline = Callee->getInlineStrategy() == AlwaysInline ||
-                      Callee->isTransparent();
-
-  // Only inline if we decided to inline or we are asked to inline all
-  // generic functions.
-  if (ShouldInline || EnableSILInliningOfGenerics)
-    return true;
-
-  return false;
-}
-
 /// Return true if inlining this call site into a cold block is profitable.
 bool SILPerformanceInliner::isProfitableInColdBlock(FullApplySite AI,
                                                     SILFunction *Callee) {
@@ -519,13 +482,8 @@ void SILPerformanceInliner::collectAppliesToInline(
         // The actual weight including a possible weight correction.
         Weight W(BlockWeight, WeightCorrections.lookup(AI));
 
-        bool IsGenericApply = !AI.getSubstitutions().empty();
-        bool IsProfitableToInline =
-            IsGenericApply ? isProfitableToInlineGeneric(AI, W, constTracker,
-                                                         NumCallerBlocks)
-                           : isProfitableToInlineNonGeneric(AI, W, constTracker,
-                                                            NumCallerBlocks);
-
+        bool IsProfitableToInline = isProfitableToInlineNonGeneric(
+            AI, W, constTracker, NumCallerBlocks);
         if (IsProfitableToInline)
           InitialCandidates.push_back(AI);
       }