[llvm] [DAG] Add SDPatternMatch::m_BitCast matcher (PR #123327)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `premerge-monolithic-linux` running on `premerge-linux-1` while building `llvm` at step 7 "test-build-unified-tree-check-all".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/153/builds/20049

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 7 (test-build-unified-tree-check-all) failure: test (failure)
******************** TEST 'Flang :: Lower/module_use.f90' FAILED ********************
Exit Code: 1

Command Output (stderr):
--
RUN: at line 1: rm -fr /build/buildbot/premerge-monolithic-linux/build/tools/flang/test/Lower/Output/module_use.f90.tmp && mkdir -p /build/buildbot/premerge-monolithic-linux/build/tools/flang/test/Lower/Output/module_use.f90.tmp
+ rm -fr /build/buildbot/premerge-monolithic-linux/build/tools/flang/test/Lower/Output/module_use.f90.tmp
+ mkdir -p /build/buildbot/premerge-monolithic-linux/build/tools/flang/test/Lower/Output/module_use.f90.tmp
RUN: at line 2: bbc -emit-fir -module /build/buildbot/premerge-monolithic-linux/build/tools/flang/test/Lower/Output/module_use.f90.tmp /build/buildbot/premerge-monolithic-linux/llvm-project/flang/test/Lower/module_definition.f90
+ bbc -emit-fir -module /build/buildbot/premerge-monolithic-linux/build/tools/flang/test/Lower/Output/module_use.f90.tmp /build/buildbot/premerge-monolithic-linux/llvm-project/flang/test/Lower/module_definition.f90
RUN: at line 3: bbc -emit-fir -J /build/buildbot/premerge-monolithic-linux/build/tools/flang/test/Lower/Output/module_use.f90.tmp /build/buildbot/premerge-monolithic-linux/llvm-project/flang/test/Lower/module_use.f90 -o - | /build/buildbot/premerge-monolithic-linux/build/bin/FileCheck /build/buildbot/premerge-monolithic-linux/llvm-project/flang/test/Lower/module_use.f90
+ bbc -emit-fir -J /build/buildbot/premerge-monolithic-linux/build/tools/flang/test/Lower/Output/module_use.f90.tmp /build/buildbot/premerge-monolithic-linux/llvm-project/flang/test/Lower/module_use.f90 -o -
+ /build/buildbot/premerge-monolithic-linux/build/bin/FileCheck /build/buildbot/premerge-monolithic-linux/llvm-project/flang/test/Lower/module_use.f90
/build/buildbot/premerge-monolithic-linux/llvm-project/flang/test/Lower/module_use.f90:17:15: error: CHECK-DAG: expected string not found in input
 ! CHECK-DAG: fir.address_of(@_QMm1Ey) : !fir.ref<!fir.array<100xi32>>
              ^
<stdin>:5:23: note: scanning from here
 func.func @_QPm1use() -> f32 {
                      ^
<stdin>:10:7: note: possible intended match here
 %3 = fir.address_of(@_QMm1Ex) : !fir.ref<f32>
      ^
/build/buildbot/premerge-monolithic-linux/llvm-project/flang/test/Lower/module_use.f90:44:14: error: CHECK-DAG: expected string not found in input
! CHECK-DAG: fir.global @_QMm1Ey : !fir.array<100xi32>
             ^
<stdin>:20:31: note: scanning from here
 func.func @_QPmodcommon1use() -> f32 {
                              ^
<stdin>:49:2: note: possible intended match here
 fir.global @_QMm1Ex : f32
 ^

Input file: <stdin>
Check file: /build/buildbot/premerge-monolithic-linux/llvm-project/flang/test/Lower/module_use.f90

-dump-input=help explains the following input dump.

Input was:
<<<<<<
          1: module attributes {dlti.dl_spec = #dlti.dl_spec<i32 = dense<32> : vector<2xi64>, f64 = dense<64> : vector<2xi64>, !llvm.ptr<270> = dense<32> : vector<4xi64>, f16 = dense<16> : vector<2xi64>, !llvm.ptr = dense<64> : vector<4xi64>, i1 = dense<8> : vector<2xi64>, i8 = dense<8> : vector<2xi64>, i16 = dense<16> : vector<2xi64>, i128 = dense<128> : vector<2xi64>, f80 = dense<128> : vector<2xi64>, f128 = dense<128> : vector<2xi64>, !llvm.ptr<271> = dense<32> : vector<4xi64>, !llvm.ptr<272> = dense<64> : vector<4xi64>, i64 = dense<64> : vector<2xi64>, "dlti.endianness" = "little", "dlti.stack_alignment" = 128 : i64>, fir.defaultkind = "a1c4d8i4l4r4", fir.kindmap = "", llvm.data_layout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128", llvm.ident = "flang version 20.0.0 (https://github.com/llvm/llvm-project.git bacfdcd7e0989117a3c76b040fe9efe093fa8708)", llvm.target_triple = "x86_64-unknown-linux-gnu"} { 
          2:  fir.global common @__BLNK__(dense<0> : vector<4xi8>) {alignment = 4 : i64} : !fir.array<4xi8> 
          3:  fir.global common @named1_(dense<0> : vector<4xi8>) {alignment = 4 : i64} : !fir.array<4xi8> 
          4:  fir.global common @named2_(dense<0> : vector<4xi8>) {alignment = 4 : i64} : !fir.array<4xi8> 
          5:  func.func @_QPm1use() -> f32 { 
dag:17'0                           X~~~~~~~~~ error: no match found
          6:  %c1_i32 = arith.constant 1 : i32 
dag:17'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          7:  %0 = fir.alloca i32 {adapt.valuebyref} 
dag:17'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          8:  %1 = fir.alloca f32 {bindc_name = "m1use", uniq_name = "_QFm1useEm1use"} 
...

```

</details>

https://github.com/llvm/llvm-project/pull/123327