[llvm] [GlobalIsel] Import GEP flags (PR #93850)

[Nikita Popov via llvm-commits]

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@@ -576,6 +576,11 @@ uint32_t MachineInstr::copyFlagsFromInstruction(const Instruction &I) {
       MIFlags |= MachineInstr::MIFlag::NoSWrap;
     if (TI->hasNoUnsignedWrap())
       MIFlags |= MachineInstr::MIFlag::NoUWrap;
+  } else if (const GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(&I)) {
+    if (GEP->hasNoUnsignedSignedWrap())
+      MIFlags |= MachineInstr::MIFlag::NoSWrap;
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nikic wrote:

Yes, nusw and nsw are not the same thing. You *can* transfer nsw to the scale multiplication, but not to the PTRADD, as this PR appears to be doing.

https://github.com/llvm/llvm-project/pull/93850