Request for reviews (XS): 6876037: CTW fails jdk7/hotspot/src/share/vm/opto/type.cpp:2055. assert(bits, "Use TypePtr for NULL")

[Tom Rodriguez]

Looks ok.

tom

On Jan 5, 2011, at 4:17 PM, Vladimir Kozlov wrote:

> http://cr.openjdk.java.net/~kvn/6876037/webrev
> 
> Fixed 6876037: CTW fails jdk7/hotspot/src/share/vm/opto/type.cpp:2055. assert(bits,"Use TypePtr for NULL")
> 
> Missing 0 value check in TypeRawPtr::add_offset().
> 
> CastX2P node in address expression for unsafe memory operation
> AddP(top, (CastX2P(SubI(3, loop_phi)), long) transformed into
> AddP(top, ConP#3, SubI(0, loop_phi)):
> 
> for (int idx = 0; idx < 4; idx++) {
>  unsafe.putByte(bufptr + (3-idx), b);
> 
> After loop full unroll this expression transformed
> into AddP(top, ConP#3, -3). We hit assert during type
> calculation for this node.