[LoopVectorize] Rename pass options. NFC.

Rename:
NoUnrolling to InterleaveOnlyWhenForced
and
AlwaysVectorize to !VectorizeOnlyWhenForced

Contrary to what the name 'AlwaysVectorize' suggests, it does not
unconditionally vectorize all loops, but applies a cost model to
determine whether vectorization is profitable to all loops. Hence,
passing false will disable the cost model, except when a loop is marked
with llvm.loop.vectorize.enable. The 'OnlyWhenForced' suffix (suggested
by @hfinkel in D55716) better matches this behavior.

Similarly, 'NoUnrolling' disables the profitability cost model for
interleaving (a term to distinguish it from unrolling by the
LoopUnrollPass); rename it for consistency.

Differential Revision: https://reviews.llvm.org/D55785

llvm-svn: 349513

1 files changed, 7 insertions, 6 deletions

diff --git a/llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp
index 36f1cbd36d9..ac989dd66f7 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorizationLegality.cpp
@@ -80,10 +80,11 @@ bool LoopVectorizeHints::Hint::validate(unsigned Val) {
   return false;
 }
 
-LoopVectorizeHints::LoopVectorizeHints(const Loop *L, bool DisableInterleaving,
+LoopVectorizeHints::LoopVectorizeHints(const Loop *L,
+                                       bool InterleaveOnlyWhenForced,
                                        OptimizationRemarkEmitter &ORE)
     : Width("vectorize.width", VectorizerParams::VectorizationFactor, HK_WIDTH),
-      Interleave("interleave.count", DisableInterleaving, HK_UNROLL),
+      Interleave("interleave.count", InterleaveOnlyWhenForced, HK_UNROLL),
       Force("vectorize.enable", FK_Undefined, HK_FORCE),
       IsVectorized("isvectorized", 0, HK_ISVECTORIZED), TheLoop(L), ORE(ORE) {
   // Populate values with existing loop metadata.
@@ -98,19 +99,19 @@ LoopVectorizeHints::LoopVectorizeHints(const Loop *L, bool DisableInterleaving,
     // consider the loop to have been already vectorized because there's
     // nothing more that we can do.
     IsVectorized.Value = Width.Value == 1 && Interleave.Value == 1;
-  LLVM_DEBUG(if (DisableInterleaving && Interleave.Value == 1) dbgs()
+  LLVM_DEBUG(if (InterleaveOnlyWhenForced && Interleave.Value == 1) dbgs()
              << "LV: Interleaving disabled by the pass manager\n");
 }
 
-bool LoopVectorizeHints::allowVectorization(Function *F, Loop *L,
-                                            bool AlwaysVectorize) const {
+bool LoopVectorizeHints::allowVectorization(
+    Function *F, Loop *L, bool VectorizeOnlyWhenForced) const {
   if (getForce() == LoopVectorizeHints::FK_Disabled) {
     LLVM_DEBUG(dbgs() << "LV: Not vectorizing: #pragma vectorize disable.\n");
     emitRemarkWithHints();
     return false;
   }
 
-  if (!AlwaysVectorize && getForce() != LoopVectorizeHints::FK_Enabled) {
+  if (VectorizeOnlyWhenForced && getForce() != LoopVectorizeHints::FK_Enabled) {
     LLVM_DEBUG(dbgs() << "LV: Not vectorizing: No #pragma vectorize enable.\n");
     emitRemarkWithHints();
     return false;