Fix ARM compilation after external array changes.

src/arm/stub-cache-arm.cc

Index: src/arm/stub-cache-arm.cc
===================================================================
--- src/arm/stub-cache-arm.cc	(revision 6375)
+++ src/arm/stub-cache-arm.cc	(working copy)
@@ -902,7 +902,112 @@
 }
 
 
+// Convert and store int passed in register ival to IEEE 754 single precision
+// floating point value at memory location (dst + 4 * wordoffset)
+// If VFP3 is available use it for conversion.
+static void StoreIntAsFloat(MacroAssembler* masm,
+                            Register dst,
+                            Register wordoffset,
+                            Register ival,
+                            Register fval,
+                            Register scratch1,
+                            Register scratch2) {
+  if (CpuFeatures::IsSupported(VFP3)) {
+    CpuFeatures::Scope scope(VFP3);
+    __ vmov(s0, ival);
+    __ add(scratch1, dst, Operand(wordoffset, LSL, 2));
+    __ vcvt_f32_s32(s0, s0);
+    __ vstr(s0, scratch1, 0);
+  } else {
+    Label not_special, done;
+    // Move sign bit from source to destination.  This works because the sign
+    // bit in the exponent word of the double has the same position and polarity
+    // as the 2's complement sign bit in a Smi.
+    ASSERT(kBinary32SignMask == 0x80000000u);
 
+    __ and_(fval, ival, Operand(kBinary32SignMask), SetCC);
+    // Negate value if it is negative.
+    __ rsb(ival, ival, Operand(0, RelocInfo::NONE), LeaveCC, ne);
+
+    // We have -1, 0 or 1, which we treat specially. Register ival contains
+    // absolute value: it is either equal to 1 (special case of -1 and 1),
+    // greater than 1 (not a special case) or less than 1 (special case of 0).
+    __ cmp(ival, Operand(1));
+    __ b(gt, &not_special);
+
+    // For 1 or -1 we need to or in the 0 exponent (biased).
+    static const uint32_t exponent_word_for_1 =
+        kBinary32ExponentBias << kBinary32ExponentShift;
+
+    __ orr(fval, fval, Operand(exponent_word_for_1), LeaveCC, eq);
+    __ b(&done);
+
+    __ bind(&not_special);
+    // Count leading zeros.
+    // Gets the wrong answer for 0, but we already checked for that case above.
+    Register zeros = scratch2;
+    __ CountLeadingZeros(zeros, ival, scratch1);
+
+    // Compute exponent and or it into the exponent register.
+    __ rsb(scratch1,
+           zeros,
+           Operand((kBitsPerInt - 1) + kBinary32ExponentBias));
+
+    __ orr(fval,
+           fval,
+           Operand(scratch1, LSL, kBinary32ExponentShift));
+
+    // Shift up the source chopping the top bit off.
+    __ add(zeros, zeros, Operand(1));
+    // This wouldn't work for 1 and -1 as the shift would be 32 which means 0.
+    __ mov(ival, Operand(ival, LSL, zeros));
+    // And the top (top 20 bits).
+    __ orr(fval,
+           fval,
+           Operand(ival, LSR, kBitsPerInt - kBinary32MantissaBits));
+
+    __ bind(&done);
+    __ str(fval, MemOperand(dst, wordoffset, LSL, 2));
+  }
+}
+
+
+// Convert unsigned integer with specified number of leading zeroes in binary
+// representation to IEEE 754 double.
+// Integer to convert is passed in register hiword.
+// Resulting double is returned in registers hiword:loword.
+// This functions does not work correctly for 0.
+static void GenerateUInt2Double(MacroAssembler* masm,
+                                Register hiword,
+                                Register loword,
+                                Register scratch,
+                                int leading_zeroes) {
+  const int meaningful_bits = kBitsPerInt - leading_zeroes - 1;
+  const int biased_exponent = HeapNumber::kExponentBias + meaningful_bits;
+
+  const int mantissa_shift_for_hi_word =
+      meaningful_bits - HeapNumber::kMantissaBitsInTopWord;
+
+  const int mantissa_shift_for_lo_word =
+      kBitsPerInt - mantissa_shift_for_hi_word;
+
+  __ mov(scratch, Operand(biased_exponent << HeapNumber::kExponentShift));
+  if (mantissa_shift_for_hi_word > 0) {
+    __ mov(loword, Operand(hiword, LSL, mantissa_shift_for_lo_word));
+    __ orr(hiword, scratch, Operand(hiword, LSR, mantissa_shift_for_hi_word));
+  } else {
+    __ mov(loword, Operand(0, RelocInfo::NONE));
+    __ orr(hiword, scratch, Operand(hiword, LSL, mantissa_shift_for_hi_word));
+  }
+
+  // If least significant bit of biased exponent was not 1 it was corrupted
+  // by most significant bit of mantissa so we should fix that.
+  if (!(biased_exponent & 1)) {
+    __ bic(hiword, hiword, Operand(1 << HeapNumber::kExponentShift));
+  }
+}
+
+
 #undef __
 #define __ ACCESS_MASM(masm())
 
@@ -3406,12 +3511,12 @@
 
       __ bind(&box_int_0);
       // Integer does not have leading zeros.
-      GenerateUInt2Double(masm, hiword, loword, r4, 0);
+      GenerateUInt2Double(masm(), hiword, loword, r4, 0);
       __ b(&done);
 
       __ bind(&box_int_1);
       // Integer has one leading zero.
-      GenerateUInt2Double(masm, hiword, loword, r4, 1);
+      GenerateUInt2Double(masm(), hiword, loword, r4, 1);
 
 
       __ bind(&done);
@@ -3595,7 +3700,7 @@
       break;
     case kExternalFloatArray:
       // Perform int-to-float conversion and store to memory.
-      StoreIntAsFloat(masm, r3, r4, r5, r6, r7, r9);
+      StoreIntAsFloat(masm(), r3, r4, r5, r6, r7, r9);
       break;
     default:
       UNREACHABLE();