RFR: 8320794: Emulate rest of vblendvp[sd] on ECore

[Volodymyr Paprotski]

Replace vpblendvp[sd] with macro assembler call and test in:
- `C2_MacroAssembler::vector_cast_float_to_int_special_cases_avx` (insufficient registers for 1 of 2 blends)
- `C2_MacroAssembler::vector_cast_double_to_int_special_cases_avx`
- `C2_MacroAssembler::vector_count_leading_zeros_int_avx`

Functional testing with existing and new tests:
`make test TEST="test/hotspot/jtreg/compiler/vectorapi/reshape test/hotspot/jtreg/compiler/vectorization/runner/BasicIntOpTest.java"`

Benchmarking with existing and new tests:

make test TEST="micro:org.openjdk.bench.jdk.incubator.vector.VectorFPtoIntCastOperations.microFloat256ToInteger256"
make test TEST="micro:org.openjdk.bench.jdk.incubator.vector.VectorFPtoIntCastOperations.microDouble256ToInteger256"
make test TEST="micro:org.openjdk.bench.vm.compiler.VectorBitCount.WithSuperword.intLeadingZeroCount"


Performance before:

Benchmark                                               (SIZE)   Mode  Cnt      Score     Error   Units
VectorFPtoIntCastOperations.microDouble256ToInteger256     512  thrpt    5  17271.078 ± 184.140  ops/ms
VectorFPtoIntCastOperations.microDouble256ToInteger256    1024  thrpt    5   9310.507 ±  88.136  ops/ms
VectorFPtoIntCastOperations.microFloat256ToInteger256     512  thrpt    5  11137.594 ± 19.009  ops/ms
VectorFPtoIntCastOperations.microFloat256ToInteger256    1024  thrpt    5   5425.001 ±  3.136  ops/ms
VectorBitCount.WithSuperword.intLeadingZeroCount    1024       0  thrpt    4  0.994 ± 0.002  ops/us


Performance after:

Benchmark                                               (SIZE)   Mode  Cnt      Score     Error   Units
VectorFPtoIntCastOperations.microDouble256ToInteger256     512  thrpt    5  19222.048 ± 87.622  ops/ms
VectorFPtoIntCastOperations.microDouble256ToInteger256    1024  thrpt    5   9233.245 ± 123.493  ops/ms
VectorFPtoIntCastOperations.microFloat256ToInteger256     512  thrpt    5  11672.806 ± 10.854  ops/ms
VectorFPtoIntCastOperations.microFloat256ToInteger256    1024  thrpt    5   6009.735 ± 12.173  ops/ms
VectorBitCount.WithSuperword.intLeadingZeroCount    1024       0  thrpt    4  1.039 ± 0.004  ops/us

-------------

Commit messages:
 - Fix whitespace
 - vpblend emulation continued

Changes: https://git.openjdk.org/jdk/pull/18310/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=18310&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8320794
  Stats: 65 lines in 5 files changed: 58 ins; 0 del; 7 mod
  Patch: https://git.openjdk.org/jdk/pull/18310.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/18310/head:pull/18310

PR: https://git.openjdk.org/jdk/pull/18310