RFR: 8351950: C2: masked vector MIN/MAX AVX512: SIGFPE / no valid evex tuple_table entry

[Jatin Bhateja]

PR adds missing EVEX compressed displacement attributes used for computing the scale factor (N) of compressed displacement.
AVX512 memory operand instructions use compressed disp8 encoding if the displacement is a multiple of scale (N), which depends on Vector Length, embedded broadcasting, and lane size.  Please refer to section 2.7.5 of Intel SDM for more details.

e.g., Consider two instructions, one with displacement 0x10203040 and the other with displacement 0x40, instruction operates over full 64-byte vector hence scale N = 64. Displacement of latter instruction is a multiple of scale, thus can be represented by 1 byte displacement encoding, while the former requires 4 bytes to represent displacement in instruction encoding.


1) vpternlogq $0xff,0x10203040(%r20,%r21,8),%zmm23,%zmm24
    EVEX        OP   MR   SIB       DISP       IMM
--------------|----|----|----|---------------|-----|
62 6b c1 40     25   84   ec     40 30 20 10     ff

2) vpternlogq $0xff,0x40(%r20,%r21,8),%zmm23,%zmm24
For full vector width operation, scalar matches with vector size, hence scale N = 64
effective displacement / compressed DISP8 = OFFSET(64) / 64 = 0x1 
    EVEX       OP   MR SIB    DISP     IMM
-------------|----|---|---|-----------|---|
62 6b c1 40    25  44   ec      01     ff 


Kindly review and share your feedback.

Best Regards,
Jatin

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Commit messages:
 - 8351950: C2: masked vector MIN/MAX AVX512: SIGFPE / no valid evex tuple_table entry

Changes: https://git.openjdk.org/jdk/pull/25021/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=25021&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8351950
  Stats: 4047 lines in 37 files changed: 4046 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/25021.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25021/head:pull/25021

PR: https://git.openjdk.org/jdk/pull/25021