[v8-dev] ARM: Optimize truncating division and fix sim

test/cctest/test-assembler-arm.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1421 matching lines @@
     __ nop();
   }
 
   Label target;
   __ b(eq, &target);
   __ bind(&target);
   __ nop();
 }
 
 
+#define TEST_SDIV(expected_, dividend_, divisor_) \
+    t.dividend = dividend_; \
+    t.divisor = divisor_; \
+    t.result = 0; \
+    dummy = CALL_GENERATED_CODE(f, &t, 0, 0, 0, 0); \
+    CHECK_EQ(expected_, t.result);
+
+
+TEST(18) {
+  // Test the sdiv.
+  CcTest::InitializeVM();
+  Isolate* isolate = CcTest::i_isolate();
+  HandleScope scope(isolate);
+
+  typedef struct {
+    uint32_t dividend;
+    uint32_t divisor;
+    uint32_t result;
+  } T;
+  T t;
+
+  Assembler assm(isolate, NULL, 0);
+
+  if (CpuFeatures::IsSupported(SUDIV)) {
+    CpuFeatureScope scope(&assm, SUDIV);
+
+    __ mov(r3, Operand(r0));
+
+    __ ldr(r0, MemOperand(r3, OFFSET_OF(T, dividend)));
+    __ ldr(r1, MemOperand(r3, OFFSET_OF(T, divisor)));
+
+    __ sdiv(r2, r0, r1);
+    __ str(r2, MemOperand(r3, OFFSET_OF(T, result)));
+
+  __ bx(lr);
+
+    CodeDesc desc;
+    assm.GetCode(&desc);
+    Object* code = isolate->heap()->CreateCode(
+        desc,
+        Code::ComputeFlags(Code::STUB),
+        Handle<Code>())->ToObjectChecked();
+    CHECK(code->IsCode());
+#ifdef DEBUG
+    Code::cast(code)->Print();

[ulan, 2013/12/11 13:57:10]

Is this leftover from debug?

[vincent.belliard.fr, 2013/12/11 14:20:29]

This is done in almost all the arm assembler tests.
It's always useful to see exactly what is the generated code (and furthermore,
it checks the disassembler).

[ulan, 2013/12/11 14:40:07]

OK, thanks.

+#endif
+    F3 f = FUNCTION_CAST<F3>(Code::cast(code)->entry());
+    Object* dummy;
+    TEST_SDIV(1073741824, kMinInt, -2);
+    TEST_SDIV(kMinInt, kMinInt, -1);
+    TEST_SDIV(5, 10, 2);
+    TEST_SDIV(3, 10, 3);
+    TEST_SDIV(-5, 10, -2);
+    TEST_SDIV(-3, 10, -3);
+    TEST_SDIV(-5, -10, 2);
+    TEST_SDIV(-3, -10, 3);
+    TEST_SDIV(5, -10, -2);
+    TEST_SDIV(3, -10, -3);
+    USE(dummy);
+  }
+}
+
+
+#undef TEST_SDIV
+
+
 TEST(code_relative_offset) {
   // Test extracting the offset of a label from the beginning of the code
   // in a register.
   CcTest::InitializeVM();
   Isolate* isolate = CcTest::i_isolate();
   HandleScope scope(isolate);
   // Initialize a code object that will contain the code.
   Handle<Object> code_object(isolate->heap()->undefined_value(), isolate);
 
   Assembler assm(isolate, NULL, 0);
@@ skipping 52 matching lines @@
   Handle<Code> code = isolate->factory()->NewCode(desc,
       Code::ComputeFlags(Code::STUB), code_object);
   CHECK(code->IsCode());
   F1 f = FUNCTION_CAST<F1>(code->entry());
   int res = reinterpret_cast<int>(CALL_GENERATED_CODE(f, 21, 0, 0, 0, 0));
   ::printf("f() = %d\n", res);
   CHECK_EQ(42, res);
 }
 
 #undef __