[llvm] [Clang][inlineasm] Add special support for "rm" output constraints (PR #92040)

[Bill Wendling via llvm-commits]

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@@ -496,6 +496,8 @@ class TargetPassConfig : public ImmutablePass {
 void registerCodeGenCallback(PassInstrumentationCallbacks &PIC,
                              LLVMTargetMachine &);
 
+bool usesGreedyOrDefaultRegisterAllocator();
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bwendling wrote:

The problem is that code gen from the ISel DAG messes things up enough that "just spilling" the registers isn't easy at all and will require a heinous hack. But if that's what you want, fine.

https://github.com/llvm/llvm-project/pull/92040