Commit Graph

3 Commits

Author SHA1 Message Date
Sanjay Patel 3e287b4d35 [CodeGen] convert math libcalls/builtins to equivalent LLVM intrinsics
There are 20 LLVM math intrinsics that correspond to mathlib calls according to the LangRef:
http://llvm.org/docs/LangRef.html#standard-c-library-intrinsics

We were only converting 3 mathlib calls (sqrt, fma, pow) and 12 builtin calls (ceil, copysign, 
fabs, floor, fma, fmax, fmin, nearbyint, pow, rint, round, trunc) to their intrinsic-equivalents.

This patch pulls the transforms together and handles all 20 cases. The switch is guarded by a 
check for const-ness to make sure we're not doing the transform if errno could possibly be set by
the libcall or builtin.

Differential Revision: https://reviews.llvm.org/D40044

llvm-svn: 319593
2017-12-01 23:15:52 +00:00
Sanjay Patel c5c8207eae [CodeGen] fix const-ness of builtin equivalents of <math.h> and <complex.h> functions that might set errno
This just makes const-ness of the builtins match const-ness of their lib function siblings. 
We're deferring fixing some of these that are obviously wrong to follow-up patches. 
Hopefully, the bugs are visible in the new test file (added at rL317220).

As the description in Builtins.def says: "e = const, but only when -fmath-errno=0".

This is step 2 of N to fix builtins and math calls as discussed in D39204.

Differential Revision: https://reviews.llvm.org/D39481

llvm-svn: 317265
2017-11-02 20:39:26 +00:00
Sanjay Patel 7cb25a888c [CodeGen] map sqrt libcalls to llvm.sqrt when errno is not set
The LLVM sqrt intrinsic definition changed with:
D28797
...so we don't have to use any relaxed FP settings other than errno handling.

This patch sidesteps a question raised in PR27435:
https://bugs.llvm.org/show_bug.cgi?id=27435

Is a programmer using __builtin_sqrt() invoking the compiler's intrinsic definition of sqrt or the mathlib definition of sqrt?

But we have an answer now: the builtin should match the behavior of the libm function including errno handling.

Differential Revision: https://reviews.llvm.org/D39204

llvm-svn: 317031
2017-10-31 20:19:39 +00:00