[llvm] [GISel][CombinerHelper] Push freeze through non-poison-producing operands (PR #90618)

[Matt Arsenault via llvm-commits]

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@@ -36,79 +36,19 @@ class GenericMachineInstr : public MachineInstr {
   }
 
   bool hasPoisonGeneratingFlags() const {
-    switch (getOpcode()) {
-    case TargetOpcode::G_ADD:
-    case TargetOpcode::G_SUB:
-    case TargetOpcode::G_MUL:
-    case TargetOpcode::G_SHL:
-    case TargetOpcode::G_TRUNC:
-      return getFlag(NoUWrap) || getFlag(NoSWrap);
-
-    case TargetOpcode::G_UDIV:
-    case TargetOpcode::G_SDIV:
-    case TargetOpcode::G_ASHR:
-    case TargetOpcode::G_LSHR:
-      return getFlag(IsExact);
-
-    case TargetOpcode::G_OR:
-      return getFlag(Disjoint);
-
-    case TargetOpcode::G_UITOFP:
-    case TargetOpcode::G_ZEXT:
-      return getFlag(NonNeg);
-
-    case TargetOpcode::G_FNEG:
-    case TargetOpcode::G_FADD:
-    case TargetOpcode::G_FSUB:
-    case TargetOpcode::G_FMUL:
-    case TargetOpcode::G_FDIV:
-    case TargetOpcode::G_FREM:
-    case TargetOpcode::G_FCMP:
-      return getFlag(FmNoNans) || getFlag(FmNoInfs);
-
-    default:
-      return false;
-    }
+    return getFlag(NoUWrap) || getFlag(NoSWrap) || getFlag(IsExact) ||
+           getFlag(Disjoint) || getFlag(NonNeg) || getFlag(FmNoNans) ||
+           getFlag(FmNoInfs);
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arsenm wrote:

can also just do this in one bit test on getFlags 

https://github.com/llvm/llvm-project/pull/90618