Checkpoint

Author: Andrew Haley

src/hotspot/cpu/x86/c1_MacroAssembler_x86.cpp

@@ -275,17 +275,20 @@ void C1_MacroAssembler::step_random(Register state, Register temp) {
   // One of these will be the best for a particular CPU.
 
   /* Algorithm "xor" from p. 4 of Marsaglia, "Xorshift RNGs" */
-  // movl(temp, state);
-  // sall(temp, 13);
-  // xorl(state, temp);
-  // movl(temp, state);
-  // shrl(temp, 7);
-  // xorl(state, temp);
-  // movl(temp, state);
-  // sall(temp, 5);
-  // xorl(state, temp);
-
-  if (VM_Version::supports_sse4_2()) {
+  if (getenv("APH_USE_XORSHIFT")) {
+    movl(temp, state);
+    sall(temp, 13);
+    xorl(state, temp);
+    movl(temp, state);
+    shrl(temp, 7);
+    xorl(state, temp);
+    movl(temp, state);
+    sall(temp, 5);
+    xorl(state, temp);
+    return;
+  }
+
+  if (!getenv("APH_USE_LCG") && VM_Version::supports_sse4_2()) {
     /* CRC used as a psuedo-random-number generator */
     // In effect, the CRC instruction is being used here for its
     // linear feedback shift register. It's unbeatably fast, and

src/hotspot/cpu/x86/macroAssembler_x86.cpp

@@ -4761,7 +4761,7 @@ Address MacroAssembler::argument_address(RegisterOrConstant arg_slot,
 // counter updates are not atomic.
 //
 void MacroAssembler::profile_receiver_type(Register recv, Register mdp, int mdp_offset,
-                                           addptr_32_insn_t xx) {
+                                           addptr_32_insn_t increment) {
   int base_receiver_offset   = in_bytes(ReceiverTypeData::receiver_offset(0));
   int end_receiver_offset    = in_bytes(ReceiverTypeData::receiver_offset(ReceiverTypeData::row_limit()));
   int poly_count_offset      = in_bytes(CounterData::count_offset());
@@ -4805,8 +4805,8 @@ void MacroAssembler::profile_receiver_type(Register recv, Register mdp, int mdp_
 
   // Corner case: no profile table. Increment poly counter and exit.
   if (ReceiverTypeData::row_limit() == 0) {
-    addptr(Address(mdp, poly_count_offset, Address::times_ptr), DataLayout::counter_increment);
-    BLOCK_COMMENT("} profile_receiver_type {");
+    increment(this, Address(mdp, poly_count_offset, Address::times_ptr), DataLayout::counter_increment);
+    BLOCK_COMMENT("} profile_receiver_type");
     return;
   }
 
@@ -4948,7 +4948,7 @@ void MacroAssembler::profile_receiver_type(Register recv, Register mdp, int mdp_
 
   bind(L_count_update);
   // addptr(Address(mdp, offset, Address::times_ptr), DataLayout::counter_increment);
-  xx(this, Address(mdp, offset, Address::times_ptr), DataLayout::counter_increment);
+  increment(this, Address(mdp, offset, Address::times_ptr), DataLayout::counter_increment);
 
   BLOCK_COMMENT("} profile_receiver_type");
 }

src/hotspot/cpu/x86/macroAssembler_x86.hpp

@@ -673,7 +673,7 @@ class MacroAssembler: public Assembler {
   }
   typedef void (*addptr_32_insn_t)(MacroAssembler *masm, Address dst, int32_t src);
   void profile_receiver_type(Register recv, Register mdp, int mdp_offset,
-                             addptr_32_insn_t xx = &addptr_32);
+                             addptr_32_insn_t increment = &addptr_32);
 
   // Debugging
 

src/hotspot/share/compiler/compiler_globals.hpp

@@ -388,7 +388,7 @@
           "If compilation is stopped with an error, capture diagnostic "    \
           "information at the bailout point")                               \
                                                                             \
-  product(int, ProfileCaptureRatio, 1, EXPERIMENTAL,                        \
+  product(int, ProfileCaptureRatio, 64, EXPERIMENTAL,                        \
           "Reduce and randomize tiered-compilation profile captures "       \
           "in order to reduce cache contention on shared method data. "     \
           "Must be a power of 2.")                                          \