[llvm] IPRA:Fix crash and verification failures for PLT calls (PR #196917)

[Sam Elliott via llvm-commits]

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@@ -154,7 +154,8 @@ bool RegUsageInfoPropagation::run(MachineFunction &MF) {
       };
 
       if (const Function *F = findCalledFunction(M, MI)) {
-        if (F->isDefinitionExact()) {
+        // The Function must not be preemptable.
+        if (F->isDefinitionExact() && F->isDSOLocal()) {
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lenary wrote:

It is reasonably confusing to me that we need both of these, surely `isDefinitionExact` should entail all reasons the definition might not be exact? Is the definition of that function (or what it calls) wrong?

https://github.com/llvm/llvm-project/pull/196917