ICData move to t1, removed dead code

robehn · Oct 15, 2024 · 5cc487a · 5cc487a
1 parent 4beb12d
commit 5cc487a
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Showing 2 changed files with 10 additions and 4 deletions.
diff --git a/src/hotspot/cpu/riscv/sharedRuntime_riscv.cpp b/src/hotspot/cpu/riscv/sharedRuntime_riscv.cpp
@@ -611,7 +611,6 @@ AdapterHandlerEntry* SharedRuntime::generate_i2c2i_adapters(MacroAssembler *masm
 
   const Register receiver = j_rarg0;
   const Register data = t0;
-  const Register tmp = t2;  // A call-clobbered register not used for arg passing
 
   // -------------------------------------------------------------------------
   // Generate a C2I adapter.  On entry we know xmethod holds the Method* during calls

diff --git a/src/hotspot/cpu/riscv/vtableStubs_riscv.cpp b/src/hotspot/cpu/riscv/vtableStubs_riscv.cpp
@@ -160,6 +160,13 @@ VtableStub* VtableStubs::create_itable_stub(int itable_index) {
   MacroAssembler* masm = new MacroAssembler(&cb);
   assert_cond(masm != nullptr);
 
+  // Real entry arguments:
+  //  t0: CompiledICData
+  //  j_rarg0: Receiver
+  // Make sure the move of CompiledICData from t0 to t1 is the frist thing that happens.
+  // Otherwise we risk clobber t0 as it is used as scratch.
+  __ mv(t1, t0);
+
 #if (!defined(PRODUCT) && defined(COMPILER2))
   if (CountCompiledCalls) {
     __ la(x18, ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
@@ -170,8 +177,8 @@ VtableStub* VtableStubs::create_itable_stub(int itable_index) {
   // get receiver (need to skip return address on top of stack)
   assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0");
 
-  // Entry arguments:
-  //  t0: CompiledICData
+  // Arguments from this point:
+  //  t1 (moved from t0): CompiledICData
   //  j_rarg0: Receiver
 
   // This stub is called from compiled code which has no callee-saved registers,
@@ -181,7 +188,7 @@ VtableStub* VtableStubs::create_itable_stub(int itable_index) {
   const Register resolved_klass_reg = x30; // resolved interface klass (REFC)
   const Register temp_reg           = x28;
   const Register temp_reg2          = x29;
-  const Register icdata_reg         = t0;
+  const Register icdata_reg         = t1;
 
   Label L_no_such_interface;