SILCombine: run builtin simplification as part of SILCombine

That means: make `BuiltinInst` conform to `SILCombineSimplifiable`, but still also run the legacy builtin simplification in SILCombine

Author: eeckstein

SwiftCompilerSources/Sources/Optimizer/InstructionSimplification/SimplifyBuiltin.swift

@@ -12,7 +12,7 @@
 
 import SIL
 
-extension BuiltinInst : OnoneSimplifiable {
+extension BuiltinInst : OnoneSimplifiable, SILCombineSimplifiable {
   func simplify(_ context: SimplifyContext) {
     switch id {
       case .IsConcrete:
@@ -165,6 +165,11 @@ private extension BuiltinInst {
     case .Sizeof:
       value = ty.getStaticSize(context: context)
     case .Strideof:
+      if isUsedAsStrideOfIndexRawPointer(context) {
+        // Constant folding `stride` would prevent index_raw_pointer simplification.
+        // See `simplifyIndexRawPointer` in SimplifyPointerToAddress.swift.
+        return
+      }
       value = ty.getStaticStride(context: context)
     case .Alignof:
       value = ty.getStaticAlignment(context: context)
@@ -181,7 +186,33 @@ private extension BuiltinInst {
     uses.replaceAll(with: literal, context)
     context.erase(instruction: self)
   }
-  
+
+  private func isUsedAsStrideOfIndexRawPointer(_ context: SimplifyContext) -> Bool {
+    var worklist = ValueWorklist(context)
+    defer { worklist.deinitialize() }
+    worklist.pushIfNotVisited(self)
+    while let v = worklist.pop() {
+      for use in v.uses {
+        switch use.instruction {
+        case let builtin as BuiltinInst:
+          switch builtin.id {
+          case .SMulOver, .TruncOrBitCast, .SExtOrBitCast, .ZExtOrBitCast:
+            worklist.pushIfNotVisited(builtin)
+          default:
+            break
+          }
+        case let tupleExtract as TupleExtractInst where tupleExtract.fieldIndex == 0:
+          worklist.pushIfNotVisited(tupleExtract)
+        case is IndexRawPointerInst:
+          return true
+        default:
+          break
+        }
+      }
+    }
+    return false
+  }
+
   func optimizeArgumentToThinMetatype(argument: Int, _ context: SimplifyContext) {
     let type: Type
 

SwiftCompilerSources/Sources/Optimizer/PassManager/PassRegistration.swift

@@ -111,6 +111,7 @@ private func registerSwiftPasses() {
   // Instruction passes
   registerForSILCombine(BeginBorrowInst.self,      { run(BeginBorrowInst.self, $0) })
   registerForSILCombine(BeginCOWMutationInst.self, { run(BeginCOWMutationInst.self, $0) })
+  registerForSILCombine(BuiltinInst.self,          { run(BuiltinInst.self, $0) })
   registerForSILCombine(FixLifetimeInst.self,      { run(FixLifetimeInst.self, $0) })
   registerForSILCombine(GlobalValueInst.self,      { run(GlobalValueInst.self, $0) })
   registerForSILCombine(StrongRetainInst.self,     { run(StrongRetainInst.self, $0) })

lib/SILOptimizer/SILCombiner/SILCombiner.h

@@ -251,7 +251,6 @@ class SILCombiner :
   SILInstruction *visitPartialApplyInst(PartialApplyInst *AI);
   SILInstruction *visitBeginApplyInst(BeginApplyInst *BAI);
   SILInstruction *optimizeStringObject(BuiltinInst *BI);
-  SILInstruction *visitBuiltinInst(BuiltinInst *BI);
   SILInstruction *visitCondFailInst(CondFailInst *CFI);
   SILInstruction *visitRefToRawPointerInst(RefToRawPointerInst *RRPI);
   SILInstruction *visitUpcastInst(UpcastInst *UCI);

lib/SILOptimizer/SILCombiner/SILCombinerBuiltinVisitors.cpp

@@ -659,7 +659,7 @@ SILInstruction *SILCombiner::optimizeStringObject(BuiltinInst *BI) {
                                       setBits & andBits);
 }
 
-SILInstruction *SILCombiner::visitBuiltinInst(BuiltinInst *I) {
+SILInstruction *SILCombiner::legacyVisitBuiltinInst(BuiltinInst *I) {
   if (I->getBuiltinInfo().ID == BuiltinValueKind::CanBeObjCClass)
     return optimizeBuiltinCanBeObjCClass(I, Builder);
   if (I->getBuiltinInfo().ID == BuiltinValueKind::IsConcrete)

lib/SILOptimizer/SILCombiner/Simplifications.def

@@ -54,6 +54,7 @@ INSTRUCTION_SIMPLIFICATION(UncheckedEnumDataInst)
 INSTRUCTION_SIMPLIFICATION(WitnessMethodInst)
 INSTRUCTION_SIMPLIFICATION(EndCOWMutationAddrInst)
 INSTRUCTION_SIMPLIFICATION_WITH_LEGACY(AllocStackInst)
+INSTRUCTION_SIMPLIFICATION_WITH_LEGACY(BuiltinInst)
 INSTRUCTION_SIMPLIFICATION_WITH_LEGACY(UnconditionalCheckedCastInst)
 INSTRUCTION_SIMPLIFICATION_WITH_LEGACY(ApplyInst)
 INSTRUCTION_SIMPLIFICATION_WITH_LEGACY(TryApplyInst)

test/SILOptimizer/sil_combine.sil

@@ -2453,7 +2453,6 @@ bb0(%0 : $Builtin.Int1):
 }
 
 // CHECK-LABEL: sil @builtin_array_opt_index_raw_pointer_to_index_addr
-// CHECK:  [[MT:%.*]] = metatype $@thick Int32.Type
 // CHECK:  [[ONE:%.*]] = integer_literal $Builtin.Word, 1
 // CHECK:  [[PTA1:%.*]] = pointer_to_address %1 : $Builtin.RawPointer to [strict] $*Int32
 // CHECK:  [[CAST1:%.*]] = builtin "truncOrBitCast_Int64_Word"(%0 : $Builtin.Int64)
@@ -2463,7 +2462,8 @@ bb0(%0 : $Builtin.Int1):
 // CHECK:  [[CAST2:%.*]] = builtin "truncOrBitCast_Int64_Word"(%0 : $Builtin.Int64)
 // CHECK:  [[IAD2:%.*]] = index_addr [[PTA2]] : $*Int32, [[CAST2]] : $Builtin.Word
 // CHECK:  [[ATP2:%.*]] = address_to_pointer [[IAD2]] : $*Int32 to $Builtin.RawPointer
-// CHECK:  builtin "takeArrayFrontToBack"<Int32>([[MT]] : $@thick Int32.Type, [[ATP1]] : $Builtin.RawPointer, [[ATP2]] : $Builtin.RawPointer, [[ONE]] : $Builtin.Word) : $()
+// CHECK:  [[MT:%.*]] = metatype $@thin Int32.Type
+// CHECK:  builtin "takeArrayFrontToBack"<Int32>([[MT]] : $@thin Int32.Type, [[ATP1]] : $Builtin.RawPointer, [[ATP2]] : $Builtin.RawPointer, [[ONE]] : $Builtin.Word) : $()
 // CHECK: return
 
 sil @builtin_array_opt_index_raw_pointer_to_index_addr : $@convention(thin) (Builtin.Int64, Builtin.RawPointer, Builtin.RawPointer) -> () {

test/SILOptimizer/sil_combine_ossa.sil

@@ -2959,7 +2959,6 @@ bb0(%0 : $Builtin.Int1):
 }
 
 // CHECK-LABEL: sil [ossa] @builtin_array_opt_index_raw_pointer_to_index_addr :
-// CHECK:  [[MT:%.*]] = metatype $@thick Int32.Type
 // CHECK:  [[ONE:%.*]] = integer_literal $Builtin.Word, 1
 // CHECK:  [[PTA1:%.*]] = pointer_to_address %1 : $Builtin.RawPointer to [strict] $*Int32
 // CHECK:  [[CAST1:%.*]] = builtin "truncOrBitCast_Int64_Word"(%0 : $Builtin.Int64)
@@ -2969,7 +2968,8 @@ bb0(%0 : $Builtin.Int1):
 // CHECK:  [[CAST2:%.*]] = builtin "truncOrBitCast_Int64_Word"(%0 : $Builtin.Int64)
 // CHECK:  [[IAD2:%.*]] = index_addr [[PTA2]] : $*Int32, [[CAST2]] : $Builtin.Word
 // CHECK:  [[ATP2:%.*]] = address_to_pointer [[IAD2]] : $*Int32 to $Builtin.RawPointer
-// CHECK:  builtin "takeArrayFrontToBack"<Int32>([[MT]] : $@thick Int32.Type, [[ATP1]] : $Builtin.RawPointer, [[ATP2]] : $Builtin.RawPointer, [[ONE]] : $Builtin.Word) : $()
+// CHECK:  [[MT:%.*]] = metatype $@thin Int32.Type
+// CHECK:  builtin "takeArrayFrontToBack"<Int32>([[MT]] : $@thin Int32.Type, [[ATP1]] : $Builtin.RawPointer, [[ATP2]] : $Builtin.RawPointer, [[ONE]] : $Builtin.Word) : $()
 // CHECK: return
 // CHECK: } // end sil function 'builtin_array_opt_index_raw_pointer_to_index_addr'
 

test/SILOptimizer/sil_combiner_concrete_prop_all_args.sil

@@ -552,15 +552,9 @@ bb0(%0 : $*τ_0_0):
 
 // CHECK-LABEL: sil shared [noinline] @$s21existential_transform16wrap_foo_bar_cpc1as5Int32VAA21SomeClassProtocolComp_AA0h5OtherijK0p_tFTf4e_n4main0hiK0C_Tg5 : $@convention(thin) (@guaranteed SomeClassComp) -> Int32 {
 // CHECK: bb0(%0 : $SomeClassComp):
-// CHECK:  %1 = integer_literal $Builtin.Int32, 10         
-// CHECK:  %2 = integer_literal $Builtin.Int32, 20         
-// CHECK:  %3 = integer_literal $Builtin.Int1, -1          
-// CHECK:  %4 = builtin "sadd_with_overflow_Int32"(%1 : $Builtin.Int32, %2 : $Builtin.Int32, %3 : $Builtin.Int1) : $(Builtin.Int32, Builtin.Int1) 
-// CHECK:  %5 = tuple_extract %4 : $(Builtin.Int32, Builtin.Int1), 0 
-// CHECK:  %6 = tuple_extract %4 : $(Builtin.Int32, Builtin.Int1), 1 
-// CHECK:  cond_fail %6 : $Builtin.Int1                    
-// CHECK:  %8 = struct $Int32 (%5 : $Builtin.Int32)        
-// CHECK:  return %8 : $Int32                              
+// CHECK:  %1 = integer_literal $Builtin.Int32, 30         
+// CHECK:  %2 = struct $Int32 (%1 : $Builtin.Int32)        
+// CHECK:  return %2 : $Int32                              
 // CHECK: } // end sil function '$s21existential_transform16wrap_foo_bar_cpc1as5Int32VAA21SomeClassProtocolComp_AA0h5OtherijK0p_tFTf4e_n4main0hiK0C_Tg5'
 sil shared [noinline] @$s21existential_transform16wrap_foo_bar_cpc1as5Int32VAA21SomeClassProtocolComp_AA0h5OtherijK0p_tFTf4e_n : $@convention(thin) <τ_0_0 where τ_0_0 : SomeClassProtocolComp, τ_0_0 : SomeOtherClassProtocolComp> (@guaranteed τ_0_0) -> Int32 {
 bb0(%0 : $τ_0_0):
@@ -581,15 +575,9 @@ bb0(%0 : $τ_0_0):
 
 // CHECK-LABEL: sil shared [noinline] @$s21existential_transform25wrap_no_foo_bar_comp_ncpc1as5Int32VAA23SomeNoClassProtocolComp_AA0j5OtherklmN0p_tFTf4e_n4main0jklN0C_Tg5 : $@convention(thin) (@guaranteed SomeNoClassComp) -> Int32 {
 // CHECK: bb0(%0 : $SomeNoClassComp):
-// CHECK:   %1 = integer_literal $Builtin.Int32, 10         
-// CHECK:   %2 = integer_literal $Builtin.Int32, 20         
-// CHECK:   %3 = integer_literal $Builtin.Int1, -1          
-// CHECK:   %4 = builtin "sadd_with_overflow_Int32"(%1 : $Builtin.Int32, %2 : $Builtin.Int32, %3 : $Builtin.Int1) : $(Builtin.Int32, Builtin.Int1) 
-// CHECK:   %5 = tuple_extract %4 : $(Builtin.Int32, Builtin.Int1), 0 
-// CHECK:   %6 = tuple_extract %4 : $(Builtin.Int32, Builtin.Int1), 1 
-// CHECK:   cond_fail %6 : $Builtin.Int1                    
-// CHECK:   %8 = struct $Int32 (%5 : $Builtin.Int32)        
-// CHECK:   return %8 : $Int32                              
+// CHECK:   %1 = integer_literal $Builtin.Int32, 30
+// CHECK:   %2 = struct $Int32 (%1 : $Builtin.Int32)
+// CHECK:   return %2 : $Int32
 // CHECK-LABEL: } // end sil function '$s21existential_transform25wrap_no_foo_bar_comp_ncpc1as5Int32VAA23SomeNoClassProtocolComp_AA0j5OtherklmN0p_tFTf4e_n4main0jklN0C_Tg5'
 sil shared [noinline] @$s21existential_transform25wrap_no_foo_bar_comp_ncpc1as5Int32VAA23SomeNoClassProtocolComp_AA0j5OtherklmN0p_tFTf4e_n : $@convention(thin) <τ_0_0 where τ_0_0 : SomeNoClassProtocolComp, τ_0_0 : SomeOtherNoClassProtocolComp> (@in_guaranteed τ_0_0) -> Int32 {
 bb0(%0 : $*τ_0_0):