[PATCH] D107002: [PowerPC] Implement XL compatibility builtin __addex

[Lei Huang via Phabricator via cfe-commits]

lei added inline comments.


================
Comment at: llvm/lib/Target/PowerPC/P9InstrResources.td:1434
+  ADDEX,
+  ADDEX8
 )> { let Unsupported = 1; }
----------------
nemanjai wrote:
> You have added the 64-bit version of this, but it seems this is only available for 64-bit operands in 64-bit mode. Under which conditions do we need the plain `ADDEX`?
Correct, the builtin `__addex()` is only available for 64bit. 
Unless I am reading the ISA wrong, the instruction `addex` is valid for both 32bit and 64bit:
```
ForCY=0,OVis set to 1 if there is a carry out of bit 0 of the sum in 64-bit mode or there is a carry out of bit 32 of the sum in 32-bit mode, and set to 0 otherwise. OV32 is set to 1 if there is a carry out of bit 32 bit of the sum.
```


Repository:
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  https://reviews.llvm.org/D107002/new/

https://reviews.llvm.org/D107002