[llvm] [XCOFF][obj2yaml] Support SymbolAlignmentAndType as 2 separate fields in YAML. (PR #76828)

[via llvm-commits]

================
@@ -0,0 +1,95 @@
+## Check that obj2yaml can parse SymbolAlignmentAndType, SymbolAlignment, and SymbolType.
+## If either SymbolAlignment or SymbolType are specified along with SymbolAligmentAndType,
+## their values override the corresponding portions of SymbolAligmentAndType.
+
+# RUN: yaml2obj %s --docnum=1 -DMAGIC=0x01DF -DSectionOrLength=SectionOrLength -o %t32
+# RUN: obj2yaml %t32 | FileCheck %s --check-prefix=CHECK
+# RUN: yaml2obj %s --docnum=1 -DMAGIC=0x01F7 -DSectionOrLength=SectionOrLengthLo -o %t64
+# RUN: obj2yaml %t64 | FileCheck %s --check-prefix=CHECK
+
+# CHECK:        --- !XCOFF
+# CHECK-NEXT: FileHeader:
+# CHECK-NEXT:   MagicNumber:
+# CHECK:      Symbols:
+# CHECK:       - Name:            .fcn1
+# CHECK:         NumberOfAuxEntries: 1
+# CHECK-NEXT:    AuxEntries:
+# CHECK-NEXT:      - Type:            AUX_CSECT
+# CHECK:             SymbolType:      XTY_SD
+# CHECK-NEXT:        SymbolAlignment: 4
+# CHECK:       - Name:            .fcn2
+# CHECK:         NumberOfAuxEntries: 1
+# CHECK-NEXT:    AuxEntries:
+# CHECK-NEXT:      - Type:            AUX_CSECT
+# CHECK:             SymbolType:      XTY_SD
+# CHECK-NEXT:        SymbolAlignment: 2
+# CHECK:       - Name:            .fcn3
+# CHECK:         NumberOfAuxEntries: 1
+# CHECK-NEXT:    AuxEntries:
+# CHECK-NEXT:      - Type:            AUX_CSECT
+# CHECK:             SymbolType:      XTY_SD
+# CHECK-NEXT:        SymbolAlignment: 0
+# CHECK:       - Name:            .fcn4
+# CHECK:         NumberOfAuxEntries: 1
+# CHECK-NEXT:    AuxEntries:
+# CHECK-NEXT:      - Type:            AUX_CSECT
+# CHECK:             SymbolType:      XTY_SD
+# CHECK-NEXT:        SymbolAlignment: 31
+
+--- !XCOFF
+FileHeader:
+  MagicNumber: [[MAGIC]]
+Symbols:
+  - StorageClass: C_FILE
+    AuxEntries:
+      - Type: AUX_FILE
+        FileNameOrString: FileName
+        FileStringType:   XFT_CD
+  - StorageClass: C_EXT
+    Name: .fcn1
+    AuxEntries:
+      - Type: AUX_CSECT
+        SymbolAlignmentAndType: 17
+        SymbolAlignment: 4
----------------
diggerlin wrote:

if user have YAML as 

```
        SymbolAlignmentAndType: 17
        SymbolAlignment: 4
```
I am prefer to emit error or warning in the test scenario.

https://github.com/llvm/llvm-project/pull/76828