ARM: Add instruction VFPCompareAndSetFlags to macro assembler

src/arm/lithium-codegen-arm.cc

 // Copyright 2010 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 1060 matching lines @@
 
   Representation r = instr->hydrogen()->representation();
   if (r.IsInteger32()) {
     Register reg = ToRegister(instr->input());
     __ cmp(reg, Operand(0));
     EmitBranch(true_block, false_block, nz);
   } else if (r.IsDouble()) {
     DoubleRegister reg = ToDoubleRegister(instr->input());
     Register scratch = scratch0();
 
-    // Test for the double value. Zero and NaN are false.
-    // Clear the Invalid cumulative exception flags.
-    __ ClearFPSCRBits(kVFPInvalidExceptionBit, scratch);
-    __ vcmp(reg, 0.0);
-      // Retrieve the exception and status flags and
-      // check for zero or an invalid exception.
-    __ vmrs(scratch);
+    // Test the double value. Zero and NaN are false.
+    __ VFPCompareAndLoadFlags(reg, 0.0, scratch);
     __ tst(scratch, Operand(kVFPZConditionFlagBit | kVFPInvalidExceptionBit));
     EmitBranch(true_block, false_block, ne);
   } else {
     ASSERT(r.IsTagged());
     Register reg = ToRegister(instr->input());
     if (instr->hydrogen()->type().IsBoolean()) {
       __ LoadRoot(ip, Heap::kTrueValueRootIndex);
       __ cmp(reg, ip);
       EmitBranch(true_block, false_block, eq);
     } else {
       Label* true_label = chunk_->GetAssemblyLabel(true_block);
       Label* false_label = chunk_->GetAssemblyLabel(false_block);
 
       __ LoadRoot(ip, Heap::kUndefinedValueRootIndex);
       __ cmp(reg, ip);
       __ b(eq, false_label);
       __ LoadRoot(ip, Heap::kTrueValueRootIndex);
       __ cmp(reg, ip);
       __ b(eq, true_label);
       __ LoadRoot(ip, Heap::kFalseValueRootIndex);
       __ cmp(reg, ip);
       __ b(eq, false_label);
       __ cmp(reg, Operand(0));
       __ b(eq, false_label);
       __ tst(reg, Operand(kSmiTagMask));
       __ b(eq, true_label);
 
-      // Test for double values. Zero and NaN are false.
+      // Test double values. Zero and NaN are false.
       Label call_stub;
       DoubleRegister dbl_scratch = d0;
       Register scratch = scratch0();
       __ ldr(scratch, FieldMemOperand(reg, HeapObject::kMapOffset));
       __ LoadRoot(ip, Heap::kHeapNumberMapRootIndex);
       __ cmp(scratch, Operand(ip));
       __ b(ne, &call_stub);
       __ sub(ip, reg, Operand(kHeapObjectTag));
       __ vldr(dbl_scratch, ip, HeapNumber::kValueOffset);
-      // Clear the Invalid cumulative exception flags.
-      __ ClearFPSCRBits(kVFPInvalidExceptionBit, scratch);
-      __ vcmp(dbl_scratch, 0.0);
-      // Retrieve the exception and status flags and
-      // check for zero or an invalid exception.
-      __ vmrs(scratch);
+      __ VFPCompareAndLoadFlags(dbl_scratch, 0.0, scratch);
       __ tst(scratch, Operand(kVFPZConditionFlagBit | kVFPInvalidExceptionBit));
       __ b(ne, false_label);
       __ b(true_label);
 
       // The conversion stub doesn't cause garbage collections so it's
       // safe to not record a safepoint after the call.
       __ bind(&call_stub);
       ToBooleanStub stub(reg);
       RegList saved_regs = kJSCallerSaved | kCalleeSaved;
       __ stm(db_w, sp, saved_regs);
@@ skipping 1049 matching lines @@
     // conversions.
     __ LoadRoot(ip, Heap::kUndefinedValueRootIndex);
     __ cmp(input_reg, Operand(ip));
     DeoptimizeIf(ne, instr->environment());
     __ mov(input_reg, Operand(0));
     __ b(&done);
 
     __ bind(&heap_number);
     __ sub(ip, input_reg, Operand(kHeapObjectTag));
     __ vldr(dbl_tmp, ip, HeapNumber::kValueOffset);
-    __ vcmp(dbl_tmp, 0.0);  // Sets overflow bit if NaN.
+    __ vcmp(dbl_tmp, 0.0);  // Sets overflow bit in FPSCR flags if NaN.
     __ vcvt_s32_f64(flt_scratch, dbl_tmp);
     __ vmov(input_reg, flt_scratch);  // 32-bit result of conversion.
     __ vmrs(pc);  // Move vector status bits to normal status bits.
     // Overflow bit is set if dbl_tmp is Nan.
     __ cmn(input_reg, Operand(1), vc);  // 0x7fffffff + 1 -> overflow.
     __ cmp(input_reg, Operand(1), vc);  // 0x80000000 - 1 -> overflow.
     DeoptimizeIf(vs, instr->environment());  // Saturation may have occured.
 
   } else {
     // Deoptimize if we don't have a heap number.
     DeoptimizeIf(ne, instr->environment());
 
     __ sub(ip, input_reg, Operand(kHeapObjectTag));
     __ vldr(dbl_tmp, ip, HeapNumber::kValueOffset);
     __ vcvt_s32_f64(flt_scratch, dbl_tmp);
     __ vmov(input_reg, flt_scratch);  // 32-bit result of conversion.
     // Non-truncating conversion means that we cannot lose bits, so we convert
     // back to check; note that using non-overlapping s and d regs would be
     // slightly faster.
     __ vcvt_f64_s32(dbl_scratch, flt_scratch);
-    __ vcmp(dbl_scratch, dbl_tmp);
-    __ vmrs(pc);  // Move vector status bits to normal status bits.
+    __ VFPCompareAndSetFlags(dbl_scratch, dbl_tmp);
     DeoptimizeIf(ne, instr->environment());  // Not equal or unordered.
     if (instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero)) {
       __ tst(input_reg, Operand(input_reg));
       __ b(ne, &done);
       __ vmov(lr, ip, dbl_tmp);
       __ tst(ip, Operand(1 << 31));  // Test sign bit.
       DeoptimizeIf(ne, instr->environment());
     }
   }
   __ bind(&done);
@@ skipping 408 matching lines @@
 
 
 void LCodeGen::DoOsrEntry(LOsrEntry* instr) {
   Abort("DoOsrEntry unimplemented.");
 }
 
 
 #undef __
 
 } }  // namespace v8::internal