src/cpu/s390/vm/macroAssembler_s390.cpp

@@ -2020,39 +2020,57 @@
 
   z_sgr(Z_SP, offset);
   z_stg(fp, _z_abi(callers_sp), Z_SP);
 }
 
-// Resize_frame with SP(new) = [addr].
-void MacroAssembler::resize_frame_absolute(Register addr, Register fp, bool load_fp) {
-  assert_different_registers(addr, fp, Z_SP);
-  if (load_fp) { z_lg(fp, _z_abi(callers_sp), Z_SP); }
-
-  if (addr != Z_R0) {
-    // Minimize stalls by not using Z_SP immediately after update.
-    z_stg(fp, _z_abi(callers_sp), addr);
-    z_lgr(Z_SP, addr);
+// Resize_frame with SP(new) = [newSP] + offset.
+//   This emitter is useful if we already have calculated a pointer
+//   into the to-be-allocated stack space, e.g. with special alignment properties,
+//   but need some additional space, e.g. for spilling.
+//   newSP    is the pre-calculated pointer. It must not be modified.
+//   fp       holds, or is filled with, the frame pointer.
+//   offset   is the additional increment which is added to addr to form the new SP.
+//            Note: specify a negative value to reserve more space!
+//   load_fp == true  only indicates that fp is not pre-filled with the frame pointer.
+//                    It does not guarantee that fp contains the frame pointer at the end.
+void MacroAssembler::resize_frame_abs_with_offset(Register newSP, Register fp, int offset, bool load_fp) {
+  assert_different_registers(newSP, fp, Z_SP);
+
+  if (load_fp) {
+    z_lg(fp, _z_abi(callers_sp), Z_SP);
+  }
+  add2reg(Z_SP, offset, newSP);
+  z_stg(fp, _z_abi(callers_sp), Z_SP);
+}
+
+// Resize_frame with SP(new) = [newSP].
+//   load_fp == true  only indicates that fp is not pre-filled with the frame pointer.
+//                    It does not guarantee that fp contains the frame pointer at the end.
+void MacroAssembler::resize_frame_absolute(Register newSP, Register fp, bool load_fp) {
+  assert_different_registers(newSP, fp, Z_SP);
+
+  if (load_fp) {
+    z_lg(fp, _z_abi(callers_sp), Z_SP); // need to use load/store.
+  }
+
+  z_lgr(Z_SP, newSP);
+  if (newSP != Z_R0) { // make sure we generate correct code, no matter what register newSP uses.
+    z_stg(fp, _z_abi(callers_sp), newSP);
   } else {
-    z_lgr(Z_SP, addr);
     z_stg(fp, _z_abi(callers_sp), Z_SP);
   }
 }
 
 // Resize_frame with SP(new) = SP(old) + offset.
 void MacroAssembler::resize_frame(RegisterOrConstant offset, Register fp, bool load_fp) {
   assert_different_registers(fp, Z_SP);
-  if (load_fp) z_lg(fp, _z_abi(callers_sp), Z_SP);
 
-  if (Displacement::is_validDisp((int)_z_abi(callers_sp) + offset.constant_or_zero())) {
-    // Minimize stalls by first using, then updating Z_SP.
-    // Do that only if we have a small positive offset or if ExtImm are available.
-    z_stg(fp, Address(Z_SP, offset, _z_abi(callers_sp)));
-    add64(Z_SP, offset);
-  } else {
+  if (load_fp) {
+    z_lg(fp, _z_abi(callers_sp), Z_SP);
+  }
     add64(Z_SP, offset);
     z_stg(fp, _z_abi(callers_sp), Z_SP);
-  }
 }
 
 void MacroAssembler::push_frame(Register bytes, Register old_sp, bool copy_sp, bool bytes_with_inverted_sign) {
 #ifdef ASSERT
   assert_different_registers(bytes, old_sp, Z_SP);

@@ -2061,36 +2079,24 @@
     asm_assert_eq("[old_sp]!=[Z_SP]", 0x211);
   }
 #endif
   if (copy_sp) { z_lgr(old_sp, Z_SP); }
   if (bytes_with_inverted_sign) {
-    z_stg(old_sp, 0, bytes, Z_SP);
-    add2reg_with_index(Z_SP, 0, bytes, Z_SP);
+    z_agr(Z_SP, bytes);
+    z_stg(old_sp, 0, Z_SP);
   } else {
     z_sgr(Z_SP, bytes); // Z_sgfr sufficient, but probably not faster.
     z_stg(old_sp, 0, Z_SP);
   }
 }
 
 unsigned int MacroAssembler::push_frame(unsigned int bytes, Register scratch) {
   long offset = Assembler::align(bytes, frame::alignment_in_bytes);
 
-  if (Displacement::is_validDisp(-offset)) {
-    // Minimize stalls by first using, then updating Z_SP.
-    // Do that only if we have ExtImm available.
-    z_stg(Z_SP, -offset, Z_SP);
-    add2reg(Z_SP, -offset);
-  } else {
-    if (scratch != Z_R0 && scratch != Z_R1) {
-      z_stg(Z_SP, -offset, Z_SP);
-      add2reg(Z_SP, -offset);
-    } else {   // scratch == Z_R0 || scratch == Z_R1
       z_lgr(scratch, Z_SP);
       add2reg(Z_SP, -offset);
       z_stg(scratch, 0, Z_SP);
-    }
-  }
   return offset;
 }
 
 // Push a frame of size `bytes' plus abi160 on top.
 unsigned int MacroAssembler::push_frame_abi160(unsigned int bytes) {

@@ -2104,10 +2110,24 @@
 void MacroAssembler::pop_frame() {
   BLOCK_COMMENT("pop_frame:");
   Assembler::z_lg(Z_SP, _z_abi(callers_sp), Z_SP);
 }
 
+// Pop current C frame and restore return PC register (Z_R14).
+void MacroAssembler::pop_frame_restore_retPC(int frame_size_in_bytes) {
+  BLOCK_COMMENT("pop_frame:");
+  int retPC_offset = _z_abi16(return_pc) + frame_size_in_bytes;
+  // If possible, pop frame by add instead of load (a penny saved is a penny got :-).
+  if (Displacement::is_validDisp(retPC_offset)) {
+    z_lg(Z_R14, retPC_offset, Z_SP);
+    add2reg(Z_SP, frame_size_in_bytes);
+  } else {
+    add2reg(Z_SP, frame_size_in_bytes);
+    restore_return_pc();
+  }
+}
+
 void MacroAssembler::call_VM_leaf_base(address entry_point, bool allow_relocation) {
   if (allow_relocation) {
     call_c(entry_point);
   } else {
     call_c_static(entry_point);