[PATCH] D71013: [AIX] Allow vararg calls when all arguments reside in registers.

[Hubert Tong via Phabricator via llvm-commits]

hubert.reinterpretcast added inline comments.


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Comment at: llvm/test/CodeGen/PowerPC/aix-cc-abi.ll:697
+  %1 = load double, double* @d1, align 8
+  call void (i32, ...) @test_vararg(i32 42, double %conv, i64 42, double %1)
+  ret void
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cebowleratibm wrote:
> ZarkoCA wrote:
> > Can one of these be set as a float? This way it's explicitly shown that floats and doubles are handled differently. 
> We could, but there's no way to do so from C code.  You can do so for typed functions, but then you don't initialize the GPR and this is outside the scope of this patch.
> 
> We could write such a test in IR with understanding nothing in C/C++ will produce such IR.
This case suggested by @ZarkoCA raises the question of how a 32-bit floating point value will be represented in a 64-bit GPR. What is the expected result? The equivalent case for XL generates a 64-bit GPR with zeroes in the high bits and the bits forming the 32-bit floating point value in the low bits.


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  https://reviews.llvm.org/D71013/new/

https://reviews.llvm.org/D71013