Merge pull request swiftlang#4819 from trentxintong/ACM

ACM compilation time improvement
abintom · Sep 16, 2016 · 38c5fbf · 38c5fbf
2 parents 0c68d0f + d00cec7
commit 38c5fbf
Showing 3 changed files with 46 additions and 10 deletions.
diff --git a/lib/SILOptimizer/Transforms/ARCCodeMotion.cpp b/lib/SILOptimizer/Transforms/ARCCodeMotion.cpp
@@ -316,6 +316,17 @@ class RetainCodeMotionContext : public CodeMotionContext {
     return false;
   }
 
+  /// Return the previous instruction if it happens to be a retain with the
+  /// given RC root, nullptr otherwise.
+  SILInstruction *getPrevReusableInst(SILInstruction *I, SILValue Root) {
+    if (&*I->getParent()->begin() == I)
+      return nullptr;
+    auto Prev = &*std::prev(SILBasicBlock::iterator(I));
+    if (isRetainInstruction(Prev) && getRCRoot(Prev) == Root)
+      return Prev;
+    return nullptr;
+  }
+
 public:
   /// Constructor.
   RetainCodeMotionContext(llvm::SpecificBumpPtrAllocator<BlockState> &BPA,
@@ -463,6 +474,13 @@ bool RetainCodeMotionContext::performCodeMotion() {
     if (Iter == InsertPoints.end())
       continue;
     for (auto IP : Iter->second) {
+      // we are about to insert a new retain instruction before the insertion
+      // point. Check if the previous instruction is reuseable, reuse it, do
+      // not insert new instruction and delete old one.
+      if (auto I = getPrevReusableInst(IP, Iter->first)) {
+        RCInstructions.erase(I);
+        continue;
+      }
       createIncrementBefore(Iter->first, IP);
       Changed = true;
     }
@@ -645,6 +663,17 @@ class ReleaseCodeMotionContext : public CodeMotionContext {
     return false;
   }
 
+  /// Return the successor instruction if it happens to be a release with the
+  /// given RC root, nullptr otherwise.
+  SILInstruction *getPrevReusableInst(SILInstruction *I, SILValue Root) {
+    if (&*I->getParent()->begin() == I)
+      return nullptr;
+    auto Prev = &*std::prev(SILBasicBlock::iterator(I));
+    if (isReleaseInstruction(Prev) && getRCRoot(Prev) == Root)
+      return Prev;
+    return nullptr;
+  }
+
 public:
   /// Constructor.
   ReleaseCodeMotionContext(llvm::SpecificBumpPtrAllocator<BlockState> &BPA,
@@ -829,6 +858,13 @@ bool ReleaseCodeMotionContext::performCodeMotion() {
     if (Iter == InsertPoints.end())
       continue;
     for (auto IP : Iter->second) {
+      // we are about to insert a new release instruction before the insertion
+      // point. Check if the successor instruction is reuseable, reuse it, do
+      // not insert new instruction and delete old one.
+      if (auto I = getPrevReusableInst(IP, Iter->first)) {
+        RCInstructions.erase(I);
+        continue;
+      }
       createDecrementBefore(Iter->first, IP);
       Changed = true;
     }

diff --git a/test/SILOptimizer/earlycodemotion.sil b/test/SILOptimizer/earlycodemotion.sil
@@ -183,7 +183,7 @@ bb3(%6 : $Builtin.Int32):
 // CHECK-NEXT: dealloc_stack
 // CHECK-NEXT: switch_enum
 // CHECK: bb1({{.*}}):
-// CHECK-NEXT: retain_value
+// CHECK: strong_retain
 // CHECK: bb2:
 // CHECK-NOT: unchecked_enum_data
 // CHECK-NOT: retain_value
@@ -382,7 +382,7 @@ bb3:
 // CHECK-NEXT: select_enum
 // CHECK-NEXT: cond_br
 // CHECK: bb1:
-// CHECK-NEXT: retain_value
+// CHECK: strong_retain
 // CHECK: bb2:
 // CHECK-NOT: unchecked_enum_data
 // CHECK-NOT: retain_value
@@ -800,9 +800,9 @@ bb3:
 //
 // CHECK-LABEL: sil @enum_simplification_test6b : $@convention(thin) (Optional<Builtin.NativeObject>) -> () {
 // CHECK: bb1:
-// CHECK: retain_value
+// CHECK: strong_retain
 // CHECK: bb2:
-// CHECK: retain_value
+// CHECK: strong_retain
 // CHECK: bb3:
 // CHECK-NOT: retain_value
 sil @enum_simplification_test6b : $@convention(thin) (Optional<Builtin.NativeObject>) -> () {
@@ -882,7 +882,7 @@ bb4:
 // CHECK-LABEL: sil @enum_simplification_test9 : $@convention(thin) (Optional<Builtin.NativeObject>) -> () {
 // CHECK: bb0([[INPUT:%[0-9]+]] : $Optional<Builtin.NativeObject>):
 // CHECK: bb1:
-// CHECK-NEXT: retain_value [[INPUT]]
+// CHECK: strong_retain
 // CHECK: bb2:
 // CHECK-NOT: retain
 // CHECK: bb3:
@@ -911,7 +911,7 @@ bb3:
 // CHECK-LABEL: sil @enum_simplification_test9_enums : $@convention(thin) (Optional<Builtin.NativeObject>) -> () {
 // CHECK: bb0([[INPUT:%[0-9]+]] : $Optional<Builtin.NativeObject>):
 // CHECK: bb1:
-// CHECK-NEXT: retain_value
+// CHECK: strong_retain
 // CHECK: bb2:
 // CHECK-NOT: retain
 // CHECK: bb3:
@@ -1508,7 +1508,7 @@ bb2(%9 : $fuzz):
 //
 // CHECK-LABEL: retain_blocked_by_copyaddr
 // CHECK: bb0
-// CHECK-NEXT: strong_retain 
+// CHECK-NEXT: retain_value 
 sil hidden @retain_blocked_by_copyaddr : $@convention(thin) <T> (@in T, B) -> @out T {
 bb0(%0 : $*T, %1 : $*T, %2 : $B):
   retain_value %2 : $B

diff --git a/test/SILOptimizer/latecodemotion.sil b/test/SILOptimizer/latecodemotion.sil
@@ -359,7 +359,7 @@ bb3(%6 : $Builtin.Int32):
 // CHECK-NEXT: dealloc_stack
 // CHECK-NEXT: switch_enum
 // CHECK: bb1({{.*}}):
-// CHECK-NEXT: retain_value
+// CHECK: strong_retain
 // CHECK: bb2:
 // CHECK-NOT: unchecked_enum_data
 // CHECK-NOT: retain_value
@@ -558,7 +558,7 @@ bb3:
 // CHECK-NEXT: select_enum
 // CHECK-NEXT: cond_br
 // CHECK: bb1:
-// CHECK-NEXT: retain_value
+// CHECK: strong_retain
 // CHECK-NOT: retain_value
 // CHECK: bb2:
 // CHECK-NOT: unchecked_enum_data
@@ -855,7 +855,7 @@ bb0(%0 : $FakeOptional<Builtin.NativeObject>):
 
 // CHECK-LABEL: sil @enum_simplification_test2 : $@convention(thin) (FakeOptional<Builtin.NativeObject>) -> () {
 // CHECK: bb0
-// CHECK: retain_value
+// CHECK: strong_retain
 // CHECK: release_value
 sil @enum_simplification_test2 : $@convention(thin) (FakeOptional<Builtin.NativeObject>) -> () {
 bb0(%0 : $FakeOptional<Builtin.NativeObject>):