src/hotspot/cpu/aarch64/sharedRuntime_aarch64.cpp

rev 60615 : 8231441: Initial SVE backend support
Reviewed-by: adinn, pli
Contributed-by: joshua.zhu@arm.com, yang.zhang@arm.com, ningsheng.jian@arm.com

*** 113,126 ****
                  reg_save_size = return_off + RegisterImpl::max_slots_per_register};
  
  };
  
  OopMap* RegisterSaver::save_live_registers(MacroAssembler* masm, int additional_frame_words, int* total_frame_words, bool save_vectors) {
  #if COMPILER2_OR_JVMCI
    if (save_vectors) {
      // Save upper half of vector registers
!     int vect_words = FloatRegisterImpl::number_of_registers * FloatRegisterImpl::extra_save_slots_per_register /
                       VMRegImpl::slots_per_word;
      additional_frame_words += vect_words;
    }
  #else
    assert(!save_vectors, "vectors are generated only by C2 and JVMCI");
--- 113,143 ----
                  reg_save_size = return_off + RegisterImpl::max_slots_per_register};
  
  };
  
  OopMap* RegisterSaver::save_live_registers(MacroAssembler* masm, int additional_frame_words, int* total_frame_words, bool save_vectors) {
+   bool use_sve = false;
+   int sve_vector_size_in_bytes = 0;
+   int sve_vector_size_in_slots = 0;
+ 
+ #ifdef COMPILER2
+   use_sve = Matcher::supports_scalable_vector();
+   sve_vector_size_in_bytes = Matcher::scalable_vector_reg_size(T_BYTE);
+   sve_vector_size_in_slots = Matcher::scalable_vector_reg_size(T_FLOAT);
+ #endif
+ 
  #if COMPILER2_OR_JVMCI
    if (save_vectors) {
+     int vect_words = 0;
+     int extra_save_slots_per_register = 0;
      // Save upper half of vector registers
!     if (use_sve) {
!       extra_save_slots_per_register = sve_vector_size_in_slots - FloatRegisterImpl::save_slots_per_register;
!     } else {
!       extra_save_slots_per_register = FloatRegisterImpl::extra_save_slots_per_neon_register;
!     }
!     vect_words = FloatRegisterImpl::number_of_registers * extra_save_slots_per_register /
                   VMRegImpl::slots_per_word;
      additional_frame_words += vect_words;
    }
  #else
    assert(!save_vectors, "vectors are generated only by C2 and JVMCI");
*** 136,146 ****
    int frame_size_in_words = frame_size_in_bytes / wordSize;
    *total_frame_words = frame_size_in_words;
  
    // Save Integer and Float registers.
    __ enter();
!   __ push_CPU_state(save_vectors);
  
    // Set an oopmap for the call site.  This oopmap will map all
    // oop-registers and debug-info registers as callee-saved.  This
    // will allow deoptimization at this safepoint to find all possible
    // debug-info recordings, as well as let GC find all oops.
--- 153,163 ----
    int frame_size_in_words = frame_size_in_bytes / wordSize;
    *total_frame_words = frame_size_in_words;
  
    // Save Integer and Float registers.
    __ enter();
!   __ push_CPU_state(save_vectors, use_sve, sve_vector_size_in_bytes);
  
    // Set an oopmap for the call site.  This oopmap will map all
    // oop-registers and debug-info registers as callee-saved.  This
    // will allow deoptimization at this safepoint to find all possible
    // debug-info recordings, as well as let GC find all oops.
*** 160,183 ****
      }
    }
  
    for (int i = 0; i < FloatRegisterImpl::number_of_registers; i++) {
      FloatRegister r = as_FloatRegister(i);
!     int sp_offset = save_vectors ? (FloatRegisterImpl::max_slots_per_register * i) :
!                                    (FloatRegisterImpl::save_slots_per_register * i);
      oop_map->set_callee_saved(VMRegImpl::stack2reg(sp_offset),
                                r->as_VMReg());
    }
  
    return oop_map;
  }
  
  void RegisterSaver::restore_live_registers(MacroAssembler* masm, bool restore_vectors) {
  #if !COMPILER2_OR_JVMCI
    assert(!restore_vectors, "vectors are generated only by C2 and JVMCI");
- #endif
    __ pop_CPU_state(restore_vectors);
    __ leave();
  
  }
  
  void RegisterSaver::restore_result_registers(MacroAssembler* masm) {
--- 177,208 ----
      }
    }
  
    for (int i = 0; i < FloatRegisterImpl::number_of_registers; i++) {
      FloatRegister r = as_FloatRegister(i);
!     int sp_offset = 0;
!     if (save_vectors) {
!       sp_offset = use_sve ? (sve_vector_size_in_slots * i) :
!                             (FloatRegisterImpl::slots_per_neon_register * i);
!     } else {
!       sp_offset = FloatRegisterImpl::save_slots_per_register * i;
!     }
      oop_map->set_callee_saved(VMRegImpl::stack2reg(sp_offset),
                                r->as_VMReg());
    }
  
    return oop_map;
  }
  
  void RegisterSaver::restore_live_registers(MacroAssembler* masm, bool restore_vectors) {
  #if !COMPILER2_OR_JVMCI
    assert(!restore_vectors, "vectors are generated only by C2 and JVMCI");
    __ pop_CPU_state(restore_vectors);
+ #else
+   __ pop_CPU_state(restore_vectors, Matcher::supports_scalable_vector(),
+                    Matcher::scalable_vector_reg_size(T_BYTE));
+ #endif
    __ leave();
  
  }
  
  void RegisterSaver::restore_result_registers(MacroAssembler* masm) {
*** 1840,1849 ****
--- 1865,1879 ----
    __ strw(rscratch1, Address(rthread, JavaThread::thread_state_offset()));
  
    // Force this write out before the read below
    __ dmb(Assembler::ISH);
  
+   if (UseSVE > 0) {
+     // Make sure that jni code does not change SVE vector length.
+     __ verify_sve_vector_length();
+   }
+ 
    // check for safepoint operation in progress and/or pending suspend requests
    Label safepoint_in_progress, safepoint_in_progress_done;
    {
      __ safepoint_poll_acquire(safepoint_in_progress);
      __ ldrw(rscratch1, Address(rthread, JavaThread::suspend_flags_offset()));
*** 2772,2781 ****
--- 2802,2817 ----
    __ reset_last_Java_frame(false);
  
    __ maybe_isb();
    __ membar(Assembler::LoadLoad | Assembler::LoadStore);
  
+   if (UseSVE > 0 && save_vectors) {
+     // Reinitialize the ptrue predicate register, in case the external runtime
+     // call clobbers ptrue reg, as we may return to SVE compiled code.
+     __ reinitialize_ptrue();
+   }
+ 
    __ ldr(rscratch1, Address(rthread, Thread::pending_exception_offset()));
    __ cbz(rscratch1, noException);
  
    // Exception pending