[lldb] Support overriding the disassembly CPU & features (#115382)

Add the ability to override the disassembly CPU and CPU features through
a target setting (`target.disassembly-cpu` and
`target.disassembly-features`) and a `disassemble` command option
(`--cpu` and `--features`).

This is especially relevant for architectures like RISC-V which relies
heavily on CPU extensions.

The majority of this patch is plumbing the options through. I recommend
looking at DisassemblerLLVMC and the test for the observable change in
behavior.

1 files changed, 4 insertions, 2 deletions

diff --git a/lldb/source/Expression/IRExecutionUnit.cpp b/lldb/source/Expression/IRExecutionUnit.cpp
index 7bee183d2ff2..9158b43b1c5c 100644
--- a/lldb/source/Expression/IRExecutionUnit.cpp
+++ b/lldb/source/Expression/IRExecutionUnit.cpp
@@ -167,8 +167,10 @@ Status IRExecutionUnit::DisassembleFunction(Stream &stream,
 
   const char *plugin_name = nullptr;
   const char *flavor_string = nullptr;
-  lldb::DisassemblerSP disassembler_sp =
-      Disassembler::FindPlugin(arch, flavor_string, plugin_name);
+  const char *cpu_string = nullptr;
+  const char *features_string = nullptr;
+  lldb::DisassemblerSP disassembler_sp = Disassembler::FindPlugin(
+      arch, flavor_string, cpu_string, features_string, plugin_name);
 
   if (!disassembler_sp) {
     ret = Status::FromErrorStringWithFormat(