[LLVMdev] Any reason why fastcc on x86 shouldn't use ECX as a return register?

Kenneth Uildriks kennethuil at gmail.com
Mon Dec 14 07:01:00 PST 2009

Now that we can safely return arbitrarily large structs on x86, it
seems to me that fastcc, which doesn't have to conform to any
preexisting ABI, should use ECX as well as EAX and EDX for returning
{i32,i32,i32} rather than use sret-demotion.

Any objections?

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