[llvm] [DAG] computeKnownFPClass - add ISD::SQRT handling + test coverage (PR #195405)

[via llvm-commits]

github-actions[bot] wrote:

<!--PREMERGE ADVISOR COMMENT: Linux-->
# :penguin: Linux x64 Test Results

* 173556 tests passed
* 3288 tests skipped
* 1 test failed

## Failed Tests
(click on a test name to see its output)

### LLVM
<details>
<summary>LLVM.CodeGen/RISCV/fold-is-fpclass-sqrt.ll</summary>

```
Exit Code: 1

Command Output (stdout):
--
# RUN: at line 2
/home/gha/actions-runner/_work/llvm-project/llvm-project/build/bin/llc -mtriple=riscv64 -mattr=+f,+d,+v -target-abi=lp64d < /home/gha/actions-runner/_work/llvm-project/llvm-project/llvm/test/CodeGen/RISCV/fold-is-fpclass-sqrt.ll | /home/gha/actions-runner/_work/llvm-project/llvm-project/build/bin/FileCheck /home/gha/actions-runner/_work/llvm-project/llvm-project/llvm/test/CodeGen/RISCV/fold-is-fpclass-sqrt.ll
# executed command: /home/gha/actions-runner/_work/llvm-project/llvm-project/build/bin/llc -mtriple=riscv64 -mattr=+f,+d,+v -target-abi=lp64d
# note: command had no output on stdout or stderr
# executed command: /home/gha/actions-runner/_work/llvm-project/llvm-project/build/bin/FileCheck /home/gha/actions-runner/_work/llvm-project/llvm-project/llvm/test/CodeGen/RISCV/fold-is-fpclass-sqrt.ll
# .---command stderr------------
# | /home/gha/actions-runner/_work/llvm-project/llvm-project/llvm/test/CodeGen/RISCV/fold-is-fpclass-sqrt.ll:38:15: error: CHECK-NEXT: expected string not found in input
# | ; CHECK-NEXT: li a0, 0
# |               ^
# | <stdin>:46:9: note: scanning from here
# | # %bb.0:
# |         ^
# | <stdin>:49:4: note: possible intended match here
# |  slli a0, a0, 60
# |    ^
# | /home/gha/actions-runner/_work/llvm-project/llvm-project/llvm/test/CodeGen/RISCV/fold-is-fpclass-sqrt.ll:100:15: error: CHECK-NEXT: expected string not found in input
# | ; CHECK-NEXT: vsetvli a0, zero, e8, mf4, ta, ma
# |               ^
# | <stdin>:119:9: note: scanning from here
# | # %bb.0:
# |         ^
# | <stdin>:120:2: note: possible intended match here
# |  vsetvli a0, zero, e32, m1, ta, ma
# |  ^
# | 
# | Input file: <stdin>
# | Check file: /home/gha/actions-runner/_work/llvm-project/llvm-project/llvm/test/CodeGen/RISCV/fold-is-fpclass-sqrt.ll
# | 
# | -dump-input=help explains the following input dump.
# | 
# | Input was:
# | <<<<<<
# |             .
# |             .
# |             .
# |            41:  .globl sqrt_nsz_negzero_f32 # -- Begin function sqrt_nsz_negzero_f32 
# |            42:  .p2align 2 
# |            43:  .type sqrt_nsz_negzero_f32, at function 
# |            44: sqrt_nsz_negzero_f32: # @sqrt_nsz_negzero_f32 
# |            45:  .cfi_startproc 
# |            46: # %bb.0: 
# | next:38'0              X error: no match found
# |            47:  fsqrt.s fa5, fa0 
# | next:38'0      ~~~~~~~~~~~~~~~~~~
# |            48:  fclass.s a0, fa5 
# | next:38'0      ~~~~~~~~~~~~~~~~~~
# |            49:  slli a0, a0, 60 
# | next:38'0      ~~~~~~~~~~~~~~~~~
# | next:38'1         ?              possible intended match
# |            50:  srli a0, a0, 63 
# | next:38'0      ~~~~~~~~~~~~~~~~~
# |            51:  ret 
# | next:38'0      ~~~~~
# |            52: .Lfunc_end3: 
# | next:38'0      ~~~~~~~~~~~~~
# |            53:  .size sqrt_nsz_negzero_f32, .Lfunc_end3-sqrt_nsz_negzero_f32 
# | next:38'0      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |            54:  .cfi_endproc 
# | next:38'0      ~~~~~~~~~~~~~~
# |             .
# |             .
# |             .
# |           114:  .p2align 2 
# |           115:  .type vsqrt_nsz_negzero_nxv2f32, at function 
# |           116:  .variant_cc vsqrt_nsz_negzero_nxv2f32 
# |           117: vsqrt_nsz_negzero_nxv2f32: # @vsqrt_nsz_negzero_nxv2f32 
# |           118:  .cfi_startproc 
# |           119: # %bb.0: 
# | next:100'0             X error: no match found
# |           120:  vsetvli a0, zero, e32, m1, ta, ma 
# | next:100'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# | next:100'1      ?                                  possible intended match
# |           121:  vfsqrt.v v8, v8 
# | next:100'0     ~~~~~~~~~~~~~~~~~
# |           122:  vfclass.v v8, v8 
# | next:100'0     ~~~~~~~~~~~~~~~~~~
# |           123:  vmseq.vi v0, v8, 8 
# | next:100'0     ~~~~~~~~~~~~~~~~~~~~
# |           124:  ret 
# | next:100'0     ~~~~~
# |           125: .Lfunc_end8: 
# | next:100'0     ~~~~~~~~~~~~~
# |             .
# |             .
# |             .
# | >>>>>>
# `-----------------------------
# error: command failed with exit status: 1

--

```
</details>

If these failures are unrelated to your changes (for example tests are broken or flaky at HEAD), please open an issue at https://github.com/llvm/llvm-project/issues and add the `infrastructure` label.

https://github.com/llvm/llvm-project/pull/195405