[llvm] [RFC][GlobalISel] Use Builders in MatchTable (PR #65955)

[via llvm-commits]

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@@ -42,17 +43,33 @@ namespace llvm {
 template <class TgtExecutor, class PredicateBitset, class ComplexMatcherMemFn,
           class CustomRendererFn>
 bool GIMatchTableExecutor::executeMatchTable(
-    TgtExecutor &Exec, NewMIVector &OutMIs, MatcherState &State,
+    TgtExecutor &Exec, MatcherState &State,
     const ExecInfoTy<PredicateBitset, ComplexMatcherMemFn, CustomRendererFn>
         &ExecInfo,
-    const int64_t *MatchTable, const TargetInstrInfo &TII,
-    MachineRegisterInfo &MRI, const TargetRegisterInfo &TRI,
-    const RegisterBankInfo &RBI, const PredicateBitset &AvailableFeatures,
-    CodeGenCoverage *CoverageInfo, GISelChangeObserver *Observer) const {
+    MachineIRBuilder &Builder, const int64_t *MatchTable,
+    const TargetInstrInfo &TII, MachineRegisterInfo &MRI,
+    const TargetRegisterInfo &TRI, const RegisterBankInfo &RBI,
+    const PredicateBitset &AvailableFeatures,
+    CodeGenCoverage *CoverageInfo) const {
+
+  // Setup observer
+  GIMatchTableObserver MTObserver;
+  GISelObserverWrapper Observer(&MTObserver);
+  if (auto *CurObs = Builder.getObserver())
+    Observer.addObserver(CurObs);
+
+  // TODO: Set MF delegate?
+
+  // Setup builder.
+  auto RestoreOldObserver = Builder.setTemporaryChangeObserver(Observer);
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qcolombet wrote:

Ditto, use the actual type.
Same thing for other `auto`s in the patch.

https://github.com/llvm/llvm-project/pull/65955