[PATCH] D79719: [AIX] Implement AIX special alignment rule about double/long double

[Jason Liu via Phabricator via cfe-commits]

jasonliu added inline comments.


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Comment at: clang/lib/AST/ASTContext.cpp:2533
+          hasFloatingPointAsFirstMember(RD, MaxFieldAlignment))
+        return std::max(ABIAlign, (unsigned)toBits(CharUnits::fromQuantity(8)));
+    }
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I guess another thing that worth considering is how we support "pragma align(nature)" in the future. It requires us to get a normal alignment for AIX which means double will be aligned 8 byte in the structure.
Right now, we always set the double to be aligned 4 byte in PPC.h, but it's not necessary the case if that pragma is in effect. How double should be aligned in a structure is really position dependent (is the structure comes after `pragma align(nature)` or `pragma align(power)`?)  I'm not very clear on how we would handle that with the current architect. 


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  https://reviews.llvm.org/D79719/new/

https://reviews.llvm.org/D79719