Lower generic MASSV entries to PowerPC subtarget-specific entries

This patch (second of two patches) lowers the generic PowerPC vector
entries to PowerPC subtarget-specific entries.
For instance, the PowerPC generic entry 'cbrtd2_massv' is lowered to
'cbrtd2_P9' or Power9 subtarget.

The first patch enables the vectorizer to recognize the IBM MASS vector
library routines. This patch specifically adds support for recognizing
the '-vector-library=MASSV' option, and defines mappings from IEEE
standard scalar math functions to generic PowerPC MASS vector
counterparts.
For instance, the generic PowerPC MASS vector entry for double-precision
'cbrt' function is '__cbrtd2_massv'

The overall support for MASS vector library is presented as such in two
patches for ease of review.

Patch by pjeeva01 (Jeeva P.)
Differential Revision: https://reviews.llvm.org/D59883

1 files changed, 4 insertions, 0 deletions

diff --git a/llvm/lib/Target/PowerPC/PPCTargetMachine.cpp b/llvm/lib/Target/PowerPC/PPCTargetMachine.cpp
index abefee8b339..40b790f27a1 100644
--- a/llvm/lib/Target/PowerPC/PPCTargetMachine.cpp
+++ b/llvm/lib/Target/PowerPC/PPCTargetMachine.cpp
@@ -119,6 +119,7 @@ extern "C" void LLVMInitializePowerPCTarget() {
   initializePPCPreEmitPeepholePass(PR);
   initializePPCTLSDynamicCallPass(PR);
   initializePPCMIPeepholePass(PR);
+  initializePPCLowerMASSVEntriesPass(PR);
 }
 
 /// Return the datalayout string of a subtarget.
@@ -401,6 +402,9 @@ void PPCPassConfig::addIRPasses() {
     addPass(createPPCBoolRetToIntPass());
   addPass(createAtomicExpandPass());
 
+  // Lower generic MASSV routines to PowerPC subtarget-specific entries.
+  addPass(createPPCLowerMASSVEntriesPass());
+  
   // For the BG/Q (or if explicitly requested), add explicit data prefetch
   // intrinsics.
   bool UsePrefetching = TM->getTargetTriple().getVendor() == Triple::BGQ &&