sret on scalars

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1

I am needing to return i128 as a shadow return due to abi issues on
alpha. The problem I am running into is the code for doing that with
scalars (currently only used for vectors, as far as I can tell) sets
the sret on the parameter. If I just go this path, then I am setting
sret on an integer pointer, which verify objects too. LangRef doesn't
say scalars are allowed to have sret set, but sret is used for
vectors.

So my question is: should I, when updating the llvm-gcc, not set sret
on my i128 shadow returns (also on f128), or should Verify accept sret
on scalar pointers, not just struct or vector pointers?

Andrew

2

Hey Andrew,

sret doesn't make sense on scalars or vectors. Where are you seeing it work with vectors?

-Chris

3

Ok. There is a a HandleScalarShadowResult, which is an implementation
subset of HandleAggregateShadowResult (has but doesn't handle the
return-shadow-pointer-from-function flag it takes). The comments and
code path led me to believe it applied to Vector types, though
Verifier didn't. Perhaps it is a dead code path, I don't know.

I guess that means I need to duplicate or generalize some stuff.

Anderw