[AddressLowering] Some small fixes.

lib/SILOptimizer/Mandatory/AddressLowering.cpp

@@ -1159,7 +1159,7 @@ void OpaqueStorageAllocation::allocatePhi(PhiValue phi) {
   coalescedPhi.coalesce(phi, pass.valueStorageMap);
 
   SmallVector<SILValue, 4> coalescedValues;
-  coalescedValues.resize(coalescedPhi.getCoalescedOperands().size());
+  coalescedValues.reserve(coalescedPhi.getCoalescedOperands().size());
   for (SILValue value : coalescedPhi.getCoalescedValues())
     coalescedValues.push_back(value);
 
@@ -3362,8 +3362,21 @@ static void rewriteFunction(AddressLoweringState &pass) {
     if (valueDef->getType().isAddress())
       continue;
 
+    SmallPtrSet<Operand *, 8> originalUses;
     SmallVector<Operand *, 8> uses(valueDef->getUses());
-    for (Operand *oper : uses) {
+    for (auto *oper : uses) {
+      originalUses.insert(oper);
+      UseRewriter::rewriteUse(oper, pass);
+    }
+    // Rewrite every new uses that was added.
+    uses.clear();
+    for (auto *use : valueDef->getUses()) {
+      if (originalUses.contains(use))
+        continue;
+      uses.push_back(use);
+    }
+    for (auto *oper : uses) {
+      assert(isa<DebugValueInst>(oper->getUser()));
       UseRewriter::rewriteUse(oper, pass);
     }
   }
@@ -3396,7 +3409,7 @@ static void filterDeadArgs(OperandValueArrayRef origArgs,
                            SmallVectorImpl<SILValue> &newArgs) {
   auto nextDeadArgI = deadArgIndices.begin();
   for (unsigned i : indices(origArgs)) {
-    if (i == *nextDeadArgI) {
+    if (i == *nextDeadArgI && nextDeadArgI != deadArgIndices.end()) {
       ++nextDeadArgI;
       continue;
     }

test/SILOptimizer/address_lowering.sil

@@ -941,15 +941,16 @@ bb0(%0 : @owned $P):
 // CHECK: bb0(%0 : $*any P):
 // CHECK:   [[ALLOCP:%.*]] = alloc_stack $any P, var, name "q"
 // CHECK:   copy_addr %0 to [init] [[ALLOCP]] : $*any P
+// CHECK:   debug_value %0 : $*any P, var, name "q"
 // CHECK:   [[OPEN:%.*]] = open_existential_addr immutable_access %0 : $*any P to $*@opened("EF755EF2-B636-11E7-B7B4-A45E60ECC541", any P) Self
 // CHECK:   [[OPTIONAL:%.*]] = alloc_stack $Optional<@opened("EF755EF2-B636-11E7-B7B4-A45E60ECC541", any P) Self>
 // CHECK:   witness_method $@opened("EF755EF2-B636-11E7-B7B4-A45E60ECC541", any P) Self, #P.foo : <Self where Self : P> (Self) -> () -> (), [[OPEN]] : $*@opened("EF755EF2-B636-11E7-B7B4-A45E60ECC541", any P) Self : $@convention(witness_method: P) <τ_0_0 where τ_0_0 : P> (@in_guaranteed τ_0_0) -> ()
 // CHECK:   [[INIT:%.*]] = init_enum_data_addr [[OPTIONAL]] : $*Optional<@opened("EF755EF2-B636-11E7-B7B4-A45E60ECC541", any P) Self>, #Optional.some!enumelt
 // CHECK:   copy_addr [[OPEN]] to [init] [[INIT]] : $*@opened("EF755EF2-B636-11E7-B7B4-A45E60ECC541", any P) Self
 // CHECK:   inject_enum_addr [[OPTIONAL]] : $*Optional<@opened("EF755EF2-B636-11E7-B7B4-A45E60ECC541", any P) Self>, #Optional.some!enumelt
 // CHECK:   [[DATA:%.*]] = unchecked_take_enum_data_addr [[OPTIONAL]] : $*Optional<@opened("EF755EF2-B636-11E7-B7B4-A45E60ECC541", any P) Self>, #Optional.some!enumelt
-// CHECK:   %10 = apply %{{.*}}<@opened("EF755EF2-B636-11E7-B7B4-A45E60ECC541", any P) Self>([[DATA]]) : $@convention(witness_method: P) <τ_0_0 where τ_0_0 : P> (@in_guaranteed τ_0_0) -> ()
-// CHECK:   destroy_addr %9 : $*@opened("EF755EF2-B636-11E7-B7B4-A45E60ECC541", any P) Self
+// CHECK:   apply %{{.*}}<@opened("EF755EF2-B636-11E7-B7B4-A45E60ECC541", any P) Self>([[DATA]]) : $@convention(witness_method: P) <τ_0_0 where τ_0_0 : P> (@in_guaranteed τ_0_0) -> ()
+// CHECK:   destroy_addr [[DATA:%[^,]+]] : $*@opened("EF755EF2-B636-11E7-B7B4-A45E60ECC541", any P) Self
 // CHECK:   destroy_addr [[ALLOCP]] : $*any P
 // CHECK:   destroy_addr %0 : $*any P
 // CHECK:   dealloc_stack [[OPTIONAL]] : $*Optional<@opened("EF755EF2-B636-11E7-B7B4-A45E60ECC541", any P) Self>

test/SILOptimizer/address_lowering_phi.sil

@@ -15,6 +15,8 @@ enum Optional<T> {
   case some(T)
 }
 
+struct S {}
+
 struct SRef<T> {
   @_hasStorage var object: AnyObject { get set }
   @_hasStorage var element: T { get set }
@@ -470,3 +472,67 @@ bb2:
 bb3(%phi : @owned $T):
   return %phi : $T
 }
+
+// Check that the debug_value instruction that is created when deleting a load
+// gets rewritten and doesn't obstruct the deletion of the phi.
+// CHECK-LABEL: sil [ossa] @f100_store_phi : {{.*}} {
+// CHECK:       {{bb[0-9]+}}({{%[^,]+}} : $*Value):
+// CHECK:         [[TEMP:%[^,]+]] = alloc_stack $Value
+// CHECK:         [[VAR:%[^,]+]] = alloc_stack [lexical] $Value, var, name "value"
+// CHECK:         cond_br undef, bb2, bb1
+// CHECK:       bb3:
+// CHECK:         copy_addr [take] [[TEMP]] to [init] [[VAR]]
+// CHECK:         debug_value [[TEMP]] : $*Value, var, name "value"
+// CHECK-LABEL: } // end sil function 'f100_store_phi'
+sil [ossa] @f100_store_phi : $@convention(thin) <Value> (@in Value) -> () {
+entry(%instance : @owned $Value):
+  %14 = alloc_stack [lexical] $Value, var, name "value"
+  cond_br undef, left, right
+
+left:
+  br merge(%instance : $Value)
+
+right:
+  br merge(%instance : $Value)
+
+merge(%34 : @owned $Value):
+  store %34 to [init] %14 : $*Value
+  destroy_addr %14 : $*Value
+  dealloc_stack %14 : $*Value
+  %43 = tuple ()
+  return %43 : $()
+}
+
+// CHECK-LABEL: sil [ossa] @f105_phi_into_tuple : {{.*}} {
+// CHECK:         [[STORAGE:%[^,]+]] = alloc_stack $(Self, Builtin.Int1)          
+// CHECK:         [[SELF_ADDR:%[^,]+]] = tuple_element_addr [[STORAGE]]
+// CHECK:         apply {{%[^,]+}}<Self>([[SELF_ADDR]])
+// CHECK-LABEL: } // end sil function 'f105_phi_into_tuple'
+sil [ossa] @f105_phi_into_tuple : $@convention(thin) <Self> () -> () {
+  %getOut = function_ref @getOut : $@convention(thin) <T> () -> @out T
+  %self = apply %getOut<Self>() : $@convention(thin) <τ_0_0> () -> @out τ_0_0
+  br exit(%self : $Self)
+
+exit(%self_2 : @owned $Self):
+  %tuple = tuple (%self_2 : $Self, undef : $Bool)
+  destroy_value %tuple : $(Self, Bool)
+  %retval = tuple ()
+  return %retval : $()
+}
+
+// Check deleting the first of multiple block arguments.
+// CHECK-LABEL: sil [ossa] @f110_nonfinal_argument : {{.*}} {
+// CHECK:       bb3({{%[^,]+}} : $S):
+// CHECK-LABEL: } // end sil function 'f110_nonfinal_argument'
+sil [ossa] @f110_nonfinal_argument : $@convention(thin) <T> (@in T, S) -> () {
+entry(%instance : @owned $T, %s : $S):
+  cond_br undef, left, right
+left:
+  br exit(%instance : $T, %s : $S)
+right:
+  br exit(%instance : $T, %s : $S)
+exit(%instance_2 : @owned $T, %s_2 : $S):
+  destroy_value %instance_2 : $T
+  %retval = tuple ()
+  return %retval : $()
+}