# HG changeset patch
# User bulasevich
# Date 1616426559 -3600
#      Mon Mar 22 16:22:39 2021 +0100
# Node ID 1effd12c479af44e3d3e36d9d1152a355a114603
# Parent  a6e68314ec2258d867568104b146fbc0655951ed
8213845: ARM32: Interpreter doesn't call result handler after native calls
Summary: Fix mapping of native jboolean result to 0..1 on ARM32
Reviewed-by: aph, phh
Contributed-by: christoph.goettschkes@microdoc.com

diff --git a/src/hotspot/cpu/arm/interpreterRT_arm.cpp b/src/hotspot/cpu/arm/interpreterRT_arm.cpp
--- a/src/hotspot/cpu/arm/interpreterRT_arm.cpp
+++ b/src/hotspot/cpu/arm/interpreterRT_arm.cpp
@@ -86,11 +86,12 @@
   // For ARM, the fast signature handler only needs to know whether
   // the return value must be unboxed. T_OBJECT and T_ARRAY need not
   // be distinguished from each other and all other return values
-  // behave like integers with respect to the handler.
+  // behave like integers with respect to the handler except T_BOOLEAN
+  // which must be mapped to the range 0..1.
   bool unbox = (ret_type == T_OBJECT) || (ret_type == T_ARRAY);
   if (unbox) {
     ret_type = T_OBJECT;
-  } else {
+  } else if (ret_type != T_BOOLEAN) {
     ret_type = T_INT;
   }
   result |= ((uint64_t) ret_type) << shift;
@@ -281,14 +282,7 @@
 
   address result_handler = Interpreter::result_handler(result_type);
 
-#ifdef AARCH64
-  __ mov_slow(R0, (address)result_handler);
-#else
-  // Check that result handlers are not real handler on ARM (0 or -1).
-  // This ensures the signature handlers do not need symbolic information.
-  assert((result_handler == NULL)||(result_handler==(address)0xffffffff),"");
   __ mov_slow(R0, (intptr_t)result_handler);
-#endif
 
   __ ret();
 }
diff --git a/src/hotspot/cpu/arm/macroAssembler_arm.cpp b/src/hotspot/cpu/arm/macroAssembler_arm.cpp
--- a/src/hotspot/cpu/arm/macroAssembler_arm.cpp
+++ b/src/hotspot/cpu/arm/macroAssembler_arm.cpp
@@ -1229,6 +1229,15 @@
   bind(done);
 }
 
+void MacroAssembler::c2bool(Register x) {
+  tst(x, 0xff);   // Only look at the lowest byte
+#ifdef AARCH64
+  cset(x, ne);
+#else
+  mov(x, 1, ne);
+#endif 
+}
+
 void MacroAssembler::null_check(Register reg, Register tmp, int offset) {
   if (needs_explicit_null_check(offset)) {
 #ifdef AARCH64
diff --git a/src/hotspot/cpu/arm/macroAssembler_arm.hpp b/src/hotspot/cpu/arm/macroAssembler_arm.hpp
--- a/src/hotspot/cpu/arm/macroAssembler_arm.hpp
+++ b/src/hotspot/cpu/arm/macroAssembler_arm.hpp
@@ -1054,6 +1054,8 @@
 #endif
   }
 
+  // C 'boolean' to Java boolean: x == 0 ? 0 : 1
+  void c2bool(Register x);
 
     // klass oop manipulations if compressed
 
diff --git a/src/hotspot/cpu/arm/sharedRuntime_arm.cpp b/src/hotspot/cpu/arm/sharedRuntime_arm.cpp
--- a/src/hotspot/cpu/arm/sharedRuntime_arm.cpp
+++ b/src/hotspot/cpu/arm/sharedRuntime_arm.cpp
@@ -1657,6 +1657,11 @@
     __ restore_default_fp_mode();
   }
 
+  // Ensure a Boolean result is mapped to 0..1
+  if (ret_type == T_BOOLEAN) {
+    __ c2bool(R0);
+  }
+
   // Do a safepoint check while thread is in transition state
   InlinedAddress safepoint_state(SafepointSynchronize::address_of_state());
   Label call_safepoint_runtime, return_to_java;
diff --git a/src/hotspot/cpu/arm/templateInterpreterGenerator_arm.cpp b/src/hotspot/cpu/arm/templateInterpreterGenerator_arm.cpp
--- a/src/hotspot/cpu/arm/templateInterpreterGenerator_arm.cpp
+++ b/src/hotspot/cpu/arm/templateInterpreterGenerator_arm.cpp
@@ -351,16 +351,12 @@
 }
 
 address TemplateInterpreterGenerator::generate_result_handler_for(BasicType type) {
-#ifdef AARCH64
   address entry = __ pc();
   switch (type) {
-    case T_BOOLEAN:
-      __ tst(R0, 0xff);
-      __ cset(R0, ne);
-      break;
-    case T_CHAR   : __ zero_extend(R0, R0, 16);  break;
-    case T_BYTE   : __ sign_extend(R0, R0,  8);  break;
-    case T_SHORT  : __ sign_extend(R0, R0, 16);  break;
+    case T_BOOLEAN: __ c2bool(R0); break;
+    case T_CHAR   : AARCH64_ONLY(__ zero_extend(R0, R0, 16);)  break;
+    case T_BYTE   : AARCH64_ONLY(__ sign_extend(R0, R0,  8);)  break;
+    case T_SHORT  : AARCH64_ONLY(__ sign_extend(R0, R0, 16);)  break;
     case T_INT    : // fall through
     case T_LONG   : // fall through
     case T_VOID   : // fall through
@@ -372,19 +368,10 @@
       // and verify it
       __ verify_oop(R0);
       break;
-    default       : ShouldNotReachHere();
+    default       : __ should_not_reach_here(); break;
   }
   __ ret();
   return entry;
-#else
-  // Result handlers are not used on 32-bit ARM
-  // since the returned value is already in appropriate format.
-  __ should_not_reach_here();  // to avoid empty code block
-
-  // The result handler non-zero indicates an object is returned and this is
-  // used in the native entry code.
-  return type == T_OBJECT ? (address)(-1) : NULL;
-#endif // AARCH64
 }
 
 address TemplateInterpreterGenerator::generate_safept_entry_for(TosState state, address runtime_entry) {
@@ -1216,14 +1203,9 @@
   // Unbox oop result, e.g. JNIHandles::resolve result if it's an oop.
   {
     Label Lnot_oop;
-#ifdef AARCH64
     __ mov_slow(Rtemp, AbstractInterpreter::result_handler(T_OBJECT));
     __ cmp(Rresult_handler, Rtemp);
     __ b(Lnot_oop, ne);
-#else // !AARCH64
-    // For ARM32, Rresult_handler is -1 for oop result, 0 otherwise.
-    __ cbz(Rresult_handler, Lnot_oop);
-#endif // !AARCH64
     Register value = AARCH64_ONLY(Rsaved_result) NOT_AARCH64(Rsaved_result_lo);
     __ resolve_jobject(value,   // value
                        Rtemp,   // tmp1
@@ -1296,25 +1278,14 @@
 
   __ blr(Rresult_handler);
 #else
-  __ cmp(Rresult_handler, 0);
-  __ ldr(R0, Address(FP, frame::interpreter_frame_oop_temp_offset * wordSize), ne);
-  __ mov(R0, Rsaved_result_lo, eq);
+  __ mov(R0, Rsaved_result_lo);
   __ mov(R1, Rsaved_result_hi);
 
 #ifdef __ABI_HARD__
   // reload native FP result
   __ fcpyd(D0, D8);
 #endif // __ABI_HARD__
-
-#ifdef ASSERT
-  if (VerifyOops) {
-    Label L;
-    __ cmp(Rresult_handler, 0);
-    __ b(L, eq);
-    __ verify_oop(R0);
-    __ bind(L);
-  }
-#endif // ASSERT
+  __ blx(Rresult_handler);
 #endif // AARCH64
 
   // Restore FP/LR, sender_sp and return