8293566: RISC-V: Clean up push and pop registers

Reviewed-by: fyang, shade

src/hotspot/cpu/riscv/gc/z/zBarrierSetAssembler_riscv.cpp

@@ -262,12 +262,12 @@ public:
     // Save registers
     __ push_reg(_gp_regs, sp);
     __ push_fp(_fp_regs, sp);
-    __ push_vp(_vp_regs, sp);
+    __ push_v(_vp_regs, sp);
   }
 
   ~ZSaveLiveRegisters() {
     // Restore registers
-    __ pop_vp(_vp_regs, sp);
+    __ pop_v(_vp_regs, sp);
     __ pop_fp(_fp_regs, sp);
     __ pop_reg(_gp_regs, sp);
   }

src/hotspot/cpu/riscv/interp_masm_riscv.cpp

@@ -915,7 +915,7 @@ void InterpreterMacroAssembler::test_method_data_pointer(Register mdp,
 void InterpreterMacroAssembler::set_method_data_pointer_for_bcp() {
   assert(ProfileInterpreter, "must be profiling interpreter");
   Label set_mdp;
-  push_reg(0xc00, sp); // save x10, x11
+  push_reg(RegSet::of(x10, x11), sp); // save x10, x11
 
   // Test MDO to avoid the call if it is NULL.
   ld(x10, Address(xmethod, in_bytes(Method::method_data_offset())));
@@ -928,7 +928,7 @@ void InterpreterMacroAssembler::set_method_data_pointer_for_bcp() {
   add(x10, x11, x10);
   sd(x10, Address(fp, frame::interpreter_frame_mdp_offset * wordSize));
   bind(set_mdp);
-  pop_reg(0xc00, sp);
+  pop_reg(RegSet::of(x10, x11), sp);
 }
 
 void InterpreterMacroAssembler::verify_method_data_pointer() {

src/hotspot/cpu/riscv/macroAssembler_riscv.cpp

@@ -946,7 +946,7 @@ int MacroAssembler::bitset_to_regs(unsigned int bitset, unsigned char* regs) {
   return count;
 }
 
-// Push lots of registers in the bit set supplied.  Don't push sp.
+// Push integer registers in the bitset supplied. Don't push sp.
 // Return the number of words pushed
 int MacroAssembler::push_reg(unsigned int bitset, Register stack) {
   DEBUG_ONLY(int words_pushed = 0;)
@@ -992,11 +992,11 @@ int MacroAssembler::pop_reg(unsigned int bitset, Register stack) {
   return count;
 }
 
-// Push float registers in the bitset, except sp.
+// Push floating-point registers in the bitset supplied.
-// Return the number of heapwords pushed.
+// Return the number of words pushed
 int MacroAssembler::push_fp(unsigned int bitset, Register stack) {
   CompressibleRegion cr(this);
-  int words_pushed = 0;
+  DEBUG_ONLY(int words_pushed = 0;)
   unsigned char regs[32];
   int count = bitset_to_regs(bitset, regs);
   int push_slots = count + (count & 1);
@@ -1007,23 +1007,24 @@ int MacroAssembler::push_fp(unsigned int bitset, Register stack) {
 
   for (int i = count - 1; i >= 0; i--) {
     fsd(as_FloatRegister(regs[i]), Address(stack, (push_slots - 1 - i) * wordSize));
-    words_pushed++;
+    DEBUG_ONLY(words_pushed++;)
   }
 
   assert(words_pushed == count, "oops, pushed(%d) != count(%d)", words_pushed, count);
+
   return count;
 }
 
 int MacroAssembler::pop_fp(unsigned int bitset, Register stack) {
   CompressibleRegion cr(this);
-  int words_popped = 0;
+  DEBUG_ONLY(int words_popped = 0;)
   unsigned char regs[32];
   int count = bitset_to_regs(bitset, regs);
   int pop_slots = count + (count & 1);
 
   for (int i = count - 1; i >= 0; i--) {
     fld(as_FloatRegister(regs[i]), Address(stack, (pop_slots - 1 - i) * wordSize));
-    words_popped++;
+    DEBUG_ONLY(words_popped++;)
   }
 
   if (count) {
@@ -1031,23 +1032,20 @@ int MacroAssembler::pop_fp(unsigned int bitset, Register stack) {
   }
 
   assert(words_popped == count, "oops, popped(%d) != count(%d)", words_popped, count);
+
   return count;
 }
 
 #ifdef COMPILER2
-int MacroAssembler::push_vp(unsigned int bitset, Register stack) {
+// Push vector registers in the bitset supplied.
+// Return the number of words pushed
+int MacroAssembler::push_v(unsigned int bitset, Register stack) {
   CompressibleRegion cr(this);
   int vector_size_in_bytes = Matcher::scalable_vector_reg_size(T_BYTE);
 
   // Scan bitset to accumulate register pairs
   unsigned char regs[32];
-  int count = 0;
+  int count = bitset_to_regs(bitset, regs);
-  for (int reg = 31; reg >= 0; reg--) {
-    if ((1U << 31) & bitset) {
-      regs[count++] = reg;
-    }
-    bitset <<= 1;
-  }
 
   for (int i = 0; i < count; i++) {
     sub(stack, stack, vector_size_in_bytes);
@@ -1057,19 +1055,13 @@ int MacroAssembler::push_vp(unsigned int bitset, Register stack) {
   return count * vector_size_in_bytes / wordSize;
 }
 
-int MacroAssembler::pop_vp(unsigned int bitset, Register stack) {
+int MacroAssembler::pop_v(unsigned int bitset, Register stack) {
   CompressibleRegion cr(this);
   int vector_size_in_bytes = Matcher::scalable_vector_reg_size(T_BYTE);
 
   // Scan bitset to accumulate register pairs
   unsigned char regs[32];
-  int count = 0;
+  int count = bitset_to_regs(bitset, regs);
-  for (int reg = 31; reg >= 0; reg--) {
-    if ((1U << 31) & bitset) {
-      regs[count++] = reg;
-    }
-    bitset <<= 1;
-  }
 
   for (int i = count - 1; i >= 0; i--) {
     vl1r_v(as_VectorRegister(regs[i]), stack);
@@ -1111,7 +1103,7 @@ void MacroAssembler::pop_call_clobbered_registers_except(RegSet exclude) {
 void MacroAssembler::push_CPU_state(bool save_vectors, int vector_size_in_bytes) {
   CompressibleRegion cr(this);
   // integer registers, except zr(x0) & ra(x1) & sp(x2) & gp(x3) & tp(x4)
-  push_reg(0xffffffe0, sp);
+  push_reg(RegSet::range(x5, x31), sp);
 
   // float registers
   addi(sp, sp, - 32 * wordSize);
@@ -1148,7 +1140,7 @@ void MacroAssembler::pop_CPU_state(bool restore_vectors, int vector_size_in_byte
   addi(sp, sp, 32 * wordSize);
 
   // integer registers, except zr(x0) & ra(x1) & sp(x2) & gp(x3) & tp(x4)
-  pop_reg(0xffffffe0, sp);
+  pop_reg(RegSet::range(x5, x31), sp);
 }
 
 static int patch_offset_in_jal(address branch, int64_t offset) {

src/hotspot/cpu/riscv/macroAssembler_riscv.hpp

@@ -473,17 +473,26 @@ class MacroAssembler: public Assembler {
   void double_blt(FloatRegister Rs1, FloatRegister Rs2, Label &l, bool is_far = false, bool is_unordered = false);
   void double_bgt(FloatRegister Rs1, FloatRegister Rs2, Label &l, bool is_far = false, bool is_unordered = false);
 
-  void push_reg(RegSet regs, Register stack) { if (regs.bits()) { push_reg(regs.bits(), stack); } }
+private:
-  void pop_reg(RegSet regs, Register stack) { if (regs.bits()) { pop_reg(regs.bits(), stack); } }
-  void push_reg(Register Rs);
-  void pop_reg(Register Rd);
   int push_reg(unsigned int bitset, Register stack);
   int pop_reg(unsigned int bitset, Register stack);
+  int push_fp(unsigned int bitset, Register stack);
+  int pop_fp(unsigned int bitset, Register stack);
+#ifdef COMPILER2
+  int push_v(unsigned int bitset, Register stack);
+  int pop_v(unsigned int bitset, Register stack);
+#endif // COMPILER2
+
+public:
+  void push_reg(Register Rs);
+  void pop_reg(Register Rd);
+  void push_reg(RegSet regs, Register stack) { if (regs.bits()) push_reg(regs.bits(), stack); }
+  void pop_reg(RegSet regs, Register stack)  { if (regs.bits()) pop_reg(regs.bits(), stack); }
   void push_fp(FloatRegSet regs, Register stack) { if (regs.bits()) push_fp(regs.bits(), stack); }
   void pop_fp(FloatRegSet regs, Register stack)  { if (regs.bits()) pop_fp(regs.bits(), stack); }
 #ifdef COMPILER2
-  void push_vp(VectorRegSet regs, Register stack) { if (regs.bits()) push_vp(regs.bits(), stack); }
+  void push_v(VectorRegSet regs, Register stack) { if (regs.bits()) push_v(regs.bits(), stack); }
-  void pop_vp(VectorRegSet regs, Register stack) { if (regs.bits()) pop_vp(regs.bits(), stack); }
+  void pop_v(VectorRegSet regs, Register stack)  { if (regs.bits()) pop_v(regs.bits(), stack); }
 #endif // COMPILER2
 
   // Push and pop everything that might be clobbered by a native
@@ -783,12 +792,6 @@ class MacroAssembler: public Assembler {
   // if [src1 < src2], dst = -1;
   void cmp_l2i(Register dst, Register src1, Register src2, Register tmp = t0);
 
-  int push_fp(unsigned int bitset, Register stack);
-  int pop_fp(unsigned int bitset, Register stack);
-
-  int push_vp(unsigned int bitset, Register stack);
-  int pop_vp(unsigned int bitset, Register stack);
-
   // vext
   void vmnot_m(VectorRegister vd, VectorRegister vs);
   void vncvt_x_x_w(VectorRegister vd, VectorRegister vs, VectorMask vm = unmasked);

src/hotspot/cpu/riscv/stubGenerator_riscv.cpp

@@ -599,7 +599,7 @@ class StubGenerator: public StubCodeGenerator {
 
     Label exit, error;
 
-    __ push_reg(0x3000, sp);   // save c_rarg2 and c_rarg3
+    __ push_reg(RegSet::of(c_rarg2, c_rarg3), sp); // save c_rarg2 and c_rarg3
 
     __ la(c_rarg2, ExternalAddress((address) StubRoutines::verify_oop_count_addr()));
     __ ld(c_rarg3, Address(c_rarg2));
@@ -635,12 +635,12 @@ class StubGenerator: public StubCodeGenerator {
     // return if everything seems ok
     __ bind(exit);
 
-    __ pop_reg(0x3000, sp);   // pop c_rarg2 and c_rarg3
+    __ pop_reg(RegSet::of(c_rarg2, c_rarg3), sp);  // pop c_rarg2 and c_rarg3
     __ ret();
 
     // handle errors
     __ bind(error);
-    __ pop_reg(0x3000, sp);   // pop c_rarg2 and c_rarg3
+    __ pop_reg(RegSet::of(c_rarg2, c_rarg3), sp); // pop c_rarg2 and c_rarg3
 
     __ push_reg(RegSet::range(x0, x31), sp);
     // debug(char* msg, int64_t pc, int64_t regs[])