[Lldb-commits] [lldb] [lldb][AArch64] Read SME2's ZT0 register from Linux core files (PR #70934)

[Jason Molenda via lldb-commits]

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@@ -339,6 +337,18 @@ bool RegisterContextCorePOSIX_arm64::ReadRegister(const RegisterInfo *reg_info,
       value.SetFromMemoryData(*reg_info, src + sizeof(sve::user_za_header),
                               reg_info->byte_size, lldb::eByteOrderLittle,
                               error);
+    } else if (m_register_info_up->IsSMERegZT(reg)) {
+      value.SetFromMemoryData(*reg_info, m_zt_data.GetDataStart(),
+                              reg_info->byte_size, lldb::eByteOrderLittle,
+                              error);
+    } else {
+      offset = reg_info->byte_offset - m_register_info_up->GetSMEOffset();
+      assert(offset < sizeof(m_sme_pseudo_regs));
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jasonmolenda wrote:

This would be someone trying to fetch a register that is at a greater offset than the register context buffer has.  My worry about the assert is more that in a non-debug/release build, there's no error checking, we'll read from past the end of the m_sme_psueo_regs buffer and copy it into value.
On the other hand, this does fall in to "this shouldn't ever happen", but maybe returning false here instead of filling in value would be the best choice.

https://github.com/llvm/llvm-project/pull/70934