8307513: C2: intrinsify Math.max(long,long) and Math.min(long,long)

src/hotspot/share/classfile/vmIntrinsics.hpp

@@ -189,6 +189,8 @@ class methodHandle;
   do_intrinsic(_minF,                     java_lang_Math,         min_name,           float2_float_signature,    F_S)   \
   do_intrinsic(_maxD,                     java_lang_Math,         max_name,           double2_double_signature,  F_S)   \
   do_intrinsic(_minD,                     java_lang_Math,         min_name,           double2_double_signature,  F_S)   \
+  do_intrinsic(_maxL,                     java_lang_Math,         max_name,           long2_long_signature,      F_S)   \
+  do_intrinsic(_minL,                     java_lang_Math,         min_name,           long2_long_signature,      F_S)   \
   do_intrinsic(_roundD,                   java_lang_Math,         round_name,         double_long_signature,     F_S)   \
   do_intrinsic(_roundF,                   java_lang_Math,         round_name,         float_int_signature,       F_S)   \
   do_intrinsic(_dcopySign,                java_lang_Math,         copySign_name,      double2_double_signature,  F_S)   \

src/hotspot/share/opto/c2compiler.cpp

@@ -633,6 +633,8 @@ bool C2Compiler::is_intrinsic_supported(vmIntrinsics::ID id) {
   case vmIntrinsics::_max:
   case vmIntrinsics::_min_strict:
   case vmIntrinsics::_max_strict:
+  case vmIntrinsics::_maxL:
+  case vmIntrinsics::_minL:
   case vmIntrinsics::_arraycopy:
   case vmIntrinsics::_arraySort:
   case vmIntrinsics::_arrayPartition:

src/hotspot/share/opto/library_call.cpp

@@ -691,17 +691,17 @@ bool LibraryCallKit::try_to_inline(int predicate) {
   case vmIntrinsics::_max:
   case vmIntrinsics::_min_strict:
   case vmIntrinsics::_max_strict:
-    return inline_min_max(intrinsic_id());
-
-  case vmIntrinsics::_maxF:
+  case vmIntrinsics::_minL:
+  case vmIntrinsics::_maxL:
   case vmIntrinsics::_minF:
-  case vmIntrinsics::_maxD:
+  case vmIntrinsics::_maxF:
   case vmIntrinsics::_minD:
-  case vmIntrinsics::_maxF_strict:
+  case vmIntrinsics::_maxD:
   case vmIntrinsics::_minF_strict:
-  case vmIntrinsics::_maxD_strict:
+  case vmIntrinsics::_maxF_strict:
   case vmIntrinsics::_minD_strict:
-      return inline_fp_min_max(intrinsic_id());
+  case vmIntrinsics::_maxD_strict:
+    return inline_min_max(intrinsic_id());
 
   case vmIntrinsics::_VectorUnaryOp:
     return inline_vector_nary_operation(1);
@@ -1942,7 +1942,78 @@ bool LibraryCallKit::inline_notify(vmIntrinsics::ID id) {
 
 //----------------------------inline_min_max-----------------------------------
 bool LibraryCallKit::inline_min_max(vmIntrinsics::ID id) {
-  set_result(generate_min_max(id, argument(0), argument(1)));
+  Node* a = nullptr;
+  Node* b = nullptr;
+  Node* n = nullptr;
+  switch (id) {
+    case vmIntrinsics::_min:
+    case vmIntrinsics::_max:
+    case vmIntrinsics::_minF:
+    case vmIntrinsics::_maxF:
+    case vmIntrinsics::_minF_strict:
+    case vmIntrinsics::_maxF_strict:
+    case vmIntrinsics::_min_strict:
+    case vmIntrinsics::_max_strict:
+      assert(callee()->signature()->size() == 2, "minF/maxF has 2 parameters of size 1 each.");
+      a = argument(0);
+      b = argument(1);
+      break;
+    case vmIntrinsics::_minD:
+    case vmIntrinsics::_maxD:
+    case vmIntrinsics::_minD_strict:
+    case vmIntrinsics::_maxD_strict:
+      assert(callee()->signature()->size() == 4, "minD/maxD has 2 parameters of size 2 each.");
+      a = round_double_node(argument(0));
+      b = round_double_node(argument(2));
+      break;
+    case vmIntrinsics::_minL:
+    case vmIntrinsics::_maxL:
+      assert(callee()->signature()->size() == 4, "minL/maxL has 2 parameters of size 2 each.");
+      a = argument(0);
+      b = argument(2);
+      break;
+    default:
+      fatal_unexpected_iid(id);
+      break;
+  }
+
+  switch (id) {
+    case vmIntrinsics::_min:
+    case vmIntrinsics::_min_strict:
+      n = new MinINode(a, b);
+      break;
+    case vmIntrinsics::_max:
+    case vmIntrinsics::_max_strict:
+      n = new MaxINode(a, b);
+      break;
+    case vmIntrinsics::_minF:
+    case vmIntrinsics::_minF_strict:
+      n = new MinFNode(a, b);
+      break;
+    case vmIntrinsics::_maxF:
+    case vmIntrinsics::_maxF_strict:
+      n = new MaxFNode(a, b);
+      break;
+    case vmIntrinsics::_minD:
+    case vmIntrinsics::_minD_strict:
+      n = new MinDNode(a, b);
+      break;
+    case vmIntrinsics::_maxD:
+    case vmIntrinsics::_maxD_strict:
+      n = new MaxDNode(a, b);
+      break;
+    case vmIntrinsics::_minL:
+      n = new MinLNode(_gvn.C, a, b);
+      break;
+    case vmIntrinsics::_maxL:
+      n = new MaxLNode(_gvn.C, a, b);
+      break;
+    default:
+      fatal_unexpected_iid(id);
+      break;
+  }
+
+  set_result(_gvn.transform(n));
   return true;
 }
 
@@ -2021,25 +2092,6 @@ bool LibraryCallKit::inline_math_unsignedMultiplyHigh() {
   return true;
 }
 
-Node*
-LibraryCallKit::generate_min_max(vmIntrinsics::ID id, Node* x0, Node* y0) {
-  Node* result_val = nullptr;
-  switch (id) {
-  case vmIntrinsics::_min:
-  case vmIntrinsics::_min_strict:
-    result_val = _gvn.transform(new MinINode(x0, y0));
-    break;
-  case vmIntrinsics::_max:
-  case vmIntrinsics::_max_strict:
-    result_val = _gvn.transform(new MaxINode(x0, y0));
-    break;
-  default:
-    fatal_unexpected_iid(id);
-    break;
-  }
-  return result_val;
-}
-
 inline int
 LibraryCallKit::classify_unsafe_addr(Node* &base, Node* &offset, BasicType type) {
   const TypePtr* base_type = TypePtr::NULL_PTR;
@@ -4456,7 +4508,7 @@ bool LibraryCallKit::inline_array_copyOf(bool is_copyOfRange) {
     if (!stopped()) {
       // How many elements will we copy from the original?
       // The answer is MinI(orig_tail, length).
-      Node* moved = generate_min_max(vmIntrinsics::_min, orig_tail, length);
+      Node* moved = _gvn.transform(new MinINode(orig_tail, length));
 
       // Generate a direct call to the right arraycopy function(s).
       // We know the copy is disjoint but we might not know if the
@@ -8477,91 +8529,6 @@ bool LibraryCallKit::inline_character_compare(vmIntrinsics::ID id) {
   return true;
 }
 
-//------------------------------inline_fp_min_max------------------------------
-bool LibraryCallKit::inline_fp_min_max(vmIntrinsics::ID id) {
-/* DISABLED BECAUSE METHOD DATA ISN'T COLLECTED PER CALL-SITE, SEE JDK-8015416.
-
-  // The intrinsic should be used only when the API branches aren't predictable,
-  // the last one performing the most important comparison. The following heuristic
-  // uses the branch statistics to eventually bail out if necessary.
-
-  ciMethodData *md = callee()->method_data();
-
-  if ( md != nullptr && md->is_mature() && md->invocation_count() > 0 ) {
-    ciCallProfile cp = caller()->call_profile_at_bci(bci());
-
-    if ( ((double)cp.count()) / ((double)md->invocation_count()) < 0.8 ) {
-      // Bail out if the call-site didn't contribute enough to the statistics.
-      return false;
-    }
-
-    uint taken = 0, not_taken = 0;
-
-    for (ciProfileData *p = md->first_data(); md->is_valid(p); p = md->next_data(p)) {
-      if (p->is_BranchData()) {
-        taken = ((ciBranchData*)p)->taken();
-        not_taken = ((ciBranchData*)p)->not_taken();
-      }
-    }
-
-    double balance = (((double)taken) - ((double)not_taken)) / ((double)md->invocation_count());
-    balance = balance < 0 ? -balance : balance;
-    if ( balance > 0.2 ) {
-      // Bail out if the most important branch is predictable enough.
-      return false;
-    }
-  }
-*/
-
-  Node *a = nullptr;
-  Node *b = nullptr;
-  Node *n = nullptr;
-  switch (id) {
-  case vmIntrinsics::_maxF:
-  case vmIntrinsics::_minF:
-  case vmIntrinsics::_maxF_strict:
-  case vmIntrinsics::_minF_strict:
-    assert(callee()->signature()->size() == 2, "minF/maxF has 2 parameters of size 1 each.");
-    a = argument(0);
-    b = argument(1);
-    break;
-  case vmIntrinsics::_maxD:
-  case vmIntrinsics::_minD:
-  case vmIntrinsics::_maxD_strict:
-  case vmIntrinsics::_minD_strict:
-    assert(callee()->signature()->size() == 4, "minD/maxD has 2 parameters of size 2 each.");
-    a = round_double_node(argument(0));
-    b = round_double_node(argument(2));
-    break;
-  default:
-    fatal_unexpected_iid(id);
-    break;
-  }
-  switch (id) {
-  case vmIntrinsics::_maxF:
-  case vmIntrinsics::_maxF_strict:
-    n = new MaxFNode(a, b);
-    break;
-  case vmIntrinsics::_minF:
-  case vmIntrinsics::_minF_strict:
-    n = new MinFNode(a, b);
-    break;
-  case vmIntrinsics::_maxD:
-  case vmIntrinsics::_maxD_strict:
-    n = new MaxDNode(a, b);
-    break;
-  case vmIntrinsics::_minD:
-  case vmIntrinsics::_minD_strict:
-    n = new MinDNode(a, b);
-    break;
-  default:
-    fatal_unexpected_iid(id);
-    break;
-  }
-  set_result(_gvn.transform(n));
-  return true;
-}
-
 bool LibraryCallKit::inline_profileBoolean() {
   Node* counts = argument(1);
   const TypeAryPtr* ary = nullptr;

src/hotspot/share/opto/library_call.hpp

@@ -223,7 +223,6 @@ class LibraryCallKit : public GraphKit {
   bool inline_math_subtractExactL(bool is_decrement);
   bool inline_min_max(vmIntrinsics::ID id);
   bool inline_notify(vmIntrinsics::ID id);
-  Node* generate_min_max(vmIntrinsics::ID id, Node* x, Node* y);
   // This returns Type::AnyPtr, RawPtr, or OopPtr.
   int classify_unsafe_addr(Node* &base, Node* &offset, BasicType type);
   Node* make_unsafe_address(Node*& base, Node* offset, BasicType type = T_ILLEGAL, bool can_cast = false);
@@ -354,7 +353,6 @@ class LibraryCallKit : public GraphKit {
   bool inline_vectorizedMismatch();
   bool inline_fma(vmIntrinsics::ID id);
   bool inline_character_compare(vmIntrinsics::ID id);
-  bool inline_fp_min_max(vmIntrinsics::ID id);
   bool inline_galoisCounterMode_AESCrypt();
   Node* inline_galoisCounterMode_AESCrypt_predicate();
 

src/java.base/share/classes/java/lang/Math.java

@@ -2033,6 +2033,7 @@ public static int max(int a, int b) {
      * @param   b   another argument.
      * @return  the larger of {@code a} and {@code b}.
      */
+    @IntrinsicCandidate
     public static long max(long a, long b) {
         return (a >= b) ? a : b;
     }
@@ -2128,6 +2129,7 @@ public static int min(int a, int b) {
      * @param   b   another argument.
      * @return  the smaller of {@code a} and {@code b}.
      */
+    @IntrinsicCandidate
     public static long min(long a, long b) {
         return (a <= b) ? a : b;
     }

test/hotspot/jtreg/compiler/c2/irTests/TestMinMaxIdentities.java

@@ -112,9 +112,11 @@ public int intMaxMax(int a, int b) {
 
     // Longs
 
-    // As Math.min/max(LL) is not intrinsified, it first needs to be transformed into CMoveL and then MinL/MaxL before
+    // As Math.min/max(LL) is not intrinsified in the backend, it first needs to be transformed into CMoveL and then MinL/MaxL before
     // the identity can be matched. However, the outer min/max is not transformed into CMove because of the CMove cost model.
-    // As JDK-8307513 adds intrinsics for the methods, the tests will be updated then.
+    // JDK-8307513 adds intrinsics for the methods such that MinL/MaxL replace the ternary operations,
+    // and this enables identities to be matched.
+    // Note that before JDK-8307513 MinL/MaxL nodes were already present before macro expansion.
 
     @Test
     @IR(applyIfPlatform = { "riscv64", "false" }, phase = { CompilePhase.BEFORE_MACRO_EXPANSION }, counts = { IRNode.MIN_L, "1" })
@@ -123,13 +125,13 @@ public long longMinMin(long a, long b) {
     }
 
     @Test
-    @IR(applyIfPlatform = { "riscv64", "false" }, phase = { CompilePhase.BEFORE_MACRO_EXPANSION }, counts = { IRNode.MIN_L, "1" })
+    @IR(failOn = { IRNode.MIN_L, IRNode.MAX_L })
     public long longMinMax(long a, long b) {
         return Math.min(a, Math.max(a, b));
     }
 
     @Test
-    @IR(applyIfPlatform = { "riscv64", "false" }, phase = { CompilePhase.BEFORE_MACRO_EXPANSION }, counts = { IRNode.MAX_L, "1" })
+    @IR(failOn = { IRNode.MIN_L, IRNode.MAX_L })
     public long longMaxMin(long a, long b) {
         return Math.max(a, Math.min(a, b));
     }