Prevent deopt on double value assignment to typed arrays

src/arm/stub-cache-arm.cc

Index: src/arm/stub-cache-arm.cc
diff --git a/src/arm/stub-cache-arm.cc b/src/arm/stub-cache-arm.cc
index 7fd229570a62842bffd3d80bed1a0dfd5933286b..065af25614cb7133d9326d5edc6fe0246d57a040 100644
--- a/src/arm/stub-cache-arm.cc
+++ b/src/arm/stub-cache-arm.cc
@@ -3926,27 +3926,17 @@ void KeyedStoreStubCompiler::GenerateStoreExternalArray(
         __ add(r5, r3, Operand(r4, LSL, 3));
         __ vstr(d0, r5, 0);
       } else {
-        // Need to perform float-to-int conversion.
-        // Test for NaN or infinity (both give zero).
-        __ ldr(r6, FieldMemOperand(value, HeapNumber::kExponentOffset));
-
         // Hoisted load.  vldr requires offset to be a multiple of 4 so we can
         // not include -kHeapObjectTag into it.
         __ sub(r5, value, Operand(kHeapObjectTag));
         __ vldr(d0, r5, HeapNumber::kValueOffset);
 
-        __ Sbfx(r6, r6, HeapNumber::kExponentShift, HeapNumber::kExponentBits);
-        // NaNs and Infinities have all-one exponents so they sign extend to -1.
-        __ cmp(r6, Operand(-1));
-        __ mov(r5, Operand(0), LeaveCC, eq);
-
-        // Not infinity or NaN simply convert to int.
-        if (IsElementTypeSigned(array_type)) {
-          __ vcvt_s32_f64(s0, d0, kDefaultRoundToZero, ne);
-        } else {
-          __ vcvt_u32_f64(s0, d0, kDefaultRoundToZero, ne);
-        }
-        __ vmov(r5, s0, ne);
+        __ EmitECMATruncate(r5,

[Kevin Millikin (Chromium), 2011/05/26 07:53:37]

Might as well put the args all on the same line.

[danno, 2011/06/01 13:14:41]

Done.

+                            d0,
+                            s2,
+                            r6,
+                            r7,
+                            r9);
 
         switch (array_type) {
           case kExternalByteArray: