[NFCI][TableGen] Make `Intrinsic::getAttributes` table driven (#152349)

This a follow on to https://github.com/llvm/llvm-project/pull/152219 to
reduce both code and frame size of `Intrinsic::getAttributes` further.

Currently, this function consists of several switch cases (one per
unique argument attributes) that populates the local `AS` array with all
non-empty argument attributes for that intrinsic by calling
`getIntrinsicArgAttributeSet`. This change makes this code table driven
and implements `Intrinsic::getAttributes` without any switch cases,
which reduces the code size of this function on all platforms and in
addition reduces the frame size by a factor of 10 on Windows.

This is achieved by:
1. Emitting table `ArgAttrIdTable` containing a concatenated list of
`<ArgNo, AttrID>` entries across all unique arguments.
2. Emitting table `ArgAttributesInfoTable` (indexed by unique
arguments-ID) to store the starting index and number of non-empty arg
attributes.
3. Reserving unique function-ID 255 to indicate that the intrinsic has
no function attributes (to replace `HasFnAttr` setup in each switch
case).
4. Using a simple table lookup and for loop to build the list of
argument and function attributes for a given intrinsic.

Experimental data shows that with release builds and assertions
disabled, this change reduces the code size for GCC and Clang builds on
Linux by ~9KB for a modest (80/152 byte) increase in frame size. For
Windows, it reduces the code size by 20KB and frame size from 4736 bytes
to 461 bytes which is 10x reduction. Actual data is as follows:

```
 Current trunk:
  Compiler                              gcc-13.3.0      clang-18.1.3      MSVC 19.43.34810.0
  code size                             0x35a9          0x370c            0x5581
  frame size                            0x120           0x118             0x1280

 table driven Intrinsic::getAttributes:
  code size                             0xcfb            0xcd0            0x1cf
  frame size                            0x1b8            0x188            0x1A0
  Total savings (code + data)           9212 bytes       9790 bytes       20119 bytes
```

Total savings above accounts for the additional data size for the 2 new
tables, which in this experiment was: `ArgAttributesInfoTable` = 314
bytes and `ArgAttrIdTable` = 888 bytes. Coupled with the earlier
https://github.com/llvm/llvm-project/pull/152219, this achieves a 46x
reduction in frame size for this function in Windows release builds.

0 files changed, 0 insertions, 0 deletions