[llvm] [Statepoint] Optimize Location structure size (PR #78600)

[Danila Malyutin via llvm-commits]

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@@ -238,7 +238,23 @@ StackMaps::parseOperand(MachineInstr::const_mop_iterator MOI,
       ++MOI;
       assert(MOI->isImm() && "Expected constant operand.");
       int64_t Imm = MOI->getImm();
-      Locs.emplace_back(Location::Constant, sizeof(int64_t), 0, Imm);
+      if (isInt<32>(Imm)) {
+        Locs.emplace_back(Location::Constant, sizeof(int64_t), 0, Imm);
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danilaml wrote:

Not sure about sizeof(int64_t). I think the size field is not really used for constants, since they are always 4 bytes, so I just kept it as 8 to reduce tests diff.

https://github.com/llvm/llvm-project/pull/78600