[llvm] [CodeGen][X86] Honor LargeEHEncoding when selecting x86-64 EH encoding (PR #210109)

[Farid Zakaria via llvm-commits]

================
@@ -150,29 +150,37 @@ void TargetLoweringObjectFileELF::Initialize(MCContext &Ctx,
                               dwarf::DW_EH_PE_sdata4
                         : dwarf::DW_EH_PE_absptr;
     break;
-  case Triple::x86_64:
-    if (TgtM.Options.MCOptions.LargeEHEncoding)
-      CM = CodeModel::Large;
+  case Triple::x86_64: {
+    // The large EH encoding forces 64-bit-wide EH pointers regardless of the
+    // code model, so treat it like the Large code model when selecting
+    // encodings below.
+    const CodeModel::Model EHCM =
+        TgtM.Options.MCOptions.LargeEHEncoding ? CodeModel::Large : CM;
     if (isPositionIndependent()) {
-      PersonalityEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
-        ((CM == CodeModel::Small || CM == CodeModel::Medium)
-         ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
+      PersonalityEncoding =
+          dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
+          ((EHCM == CodeModel::Small || EHCM == CodeModel::Medium)
+               ? dwarf::DW_EH_PE_sdata4
+               : dwarf::DW_EH_PE_sdata8);
       LSDAEncoding = dwarf::DW_EH_PE_pcrel |
-        (CM == CodeModel::Small
-         ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
+                     (EHCM == CodeModel::Small ? dwarf::DW_EH_PE_sdata4
+                                               : dwarf::DW_EH_PE_sdata8);
       TTypeEncoding = dwarf::DW_EH_PE_indirect | dwarf::DW_EH_PE_pcrel |
-        ((CM == CodeModel::Small || CM == CodeModel::Medium)
-         ? dwarf::DW_EH_PE_sdata4 : dwarf::DW_EH_PE_sdata8);
+                      ((EHCM == CodeModel::Small || EHCM == CodeModel::Medium)
+                           ? dwarf::DW_EH_PE_sdata4
+                           : dwarf::DW_EH_PE_sdata8);
     } else {
       PersonalityEncoding =
-        (CM == CodeModel::Small || CM == CodeModel::Medium)
-        ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
-      LSDAEncoding = (CM == CodeModel::Small)
-        ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
-      TTypeEncoding = (CM == CodeModel::Small)
-        ? dwarf::DW_EH_PE_udata4 : dwarf::DW_EH_PE_absptr;
+          (EHCM == CodeModel::Small || EHCM == CodeModel::Medium)
+              ? dwarf::DW_EH_PE_udata4
+              : dwarf::DW_EH_PE_absptr;
+      LSDAEncoding = (EHCM == CodeModel::Small) ? dwarf::DW_EH_PE_udata4
+                                                : dwarf::DW_EH_PE_absptr;
+      TTypeEncoding = (EHCM == CodeModel::Small) ? dwarf::DW_EH_PE_udata4
+                                                 : dwarf::DW_EH_PE_absptr;
----------------
fzakaria wrote:

clang-format flagged this whole section now to be reformatted.

https://github.com/llvm/llvm-project/pull/210109