RFR: 8283667: [vectorapi] Vectorization for masked load with IOOBE with predicate feature [v2]

[Xiaohong Gong]

On Thu, 5 May 2022 01:42:48 GMT, Xiaohong Gong <xgong at openjdk.org> wrote:

> > > Yeah, I agree that it's not good by adding a branch checking for `offsetInRange`. But actually I met the constant issue that passing the values all the way cannot guarantee the argument a constant in compiler at the compile time. Do you have any better idea to fixing this?
> > 
> > 
> > That's odd, `boolean` constants are passed that are then converted to `int` constants. Did you try passing integer constants all the way through?
> 
> I will try again. I remember the main cause is the calling of `fromArray0` from `fromArray`, it is not annotated with `ForceInline`. The arguments might not be compiled to a constant for cases that the offset is not in the array range like tail loop.

I tried to pass the integer constant all the way, and unfortunate that the `offsetInRange` is not compiled to a constant. The following assertion in the `vectorIntrinsics.cpp` will fail:

  --- a/src/hotspot/share/opto/vectorIntrinsics.cpp
+++ b/src/hotspot/share/opto/vectorIntrinsics.cpp
@@ -1236,6 +1236,7 @@ bool LibraryCallKit::inline_vector_mem_masked_operation(bool is_store) {
     } else {
       // Masked vector load with IOOBE always uses the predicated load.
       const TypeInt* offset_in_range = gvn().type(argument(8))->isa_int();
+      assert(offset_in_range->is_con(), "not a constant");
       if (!offset_in_range->is_con()) {
         if (C->print_intrinsics()) {
           tty->print_cr("  ** missing constant: offsetInRange=%s",

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PR: https://git.openjdk.java.net/jdk/pull/8035