Testing part 2: VectorizeOnlyWhenForced code path

Author: GYT

llvm/test/Transforms/LoopVectorize/check-disabled-vectorization-msgs.ll

@@ -1,4 +1,4 @@
-; This test checks that we emit only the correct debug message and
+; This test checks that we emit only the correct debug messages and
 ; optimization remark when the loop vectorizer is disabled by loop metadata.
 
 ; REQUIRES: asserts
@@ -44,4 +44,4 @@ for.body:                                         ; preds = %entry, %for.body
 }
 
 !0 = distinct !{!0, !1}
-!1 = !{!"llvm.loop.vectorize.enable", i1 false}
+!1 = !{!"llvm.loop.vectorize.enable", i1 false}

llvm/test/Transforms/LoopVectorize/check-vectorize-forced-only-msgs.ll

@@ -0,0 +1,46 @@
+; This test checks that we emit only the correct debug messages and
+; optimization remark when the loop is not vectorized due to the 
+; vectorize-forced-only pass option being set.
+
+; REQUIRES: asserts
+; RUN: opt -passes='loop-vectorize<vectorize-forced-only>' \
+; RUN:   -pass-remarks=loop-vectorize \
+; RUN:   -pass-remarks-missed=loop-vectorize \
+; RUN:   -pass-remarks-analysis=loop-vectorize -debug -disable-output \
+; RUN:   < %s 2>&1 | FileCheck %s
+; CHECK-NOT: LV: We can vectorize this loop
+; CHECK-NOT: LV: Not vectorizing: loop hasDisableAllTransformsHint
+; CHECK-NOT: LV: [FIXME] Not vectorizing: loop vect disabled for an unknown reason
+; CHECK-NOT: LV: Not vectorizing: #pragma vectorize disable
+; CHECK-NOT: LV: Not vectorizing: Disabled/already vectorized
+; CHECK-NOT: LV: Not vectorizing: Cannot prove legality
+; CHECK: LV: Loop hints: force=?
+; CHECK: LV: Not vectorizing: VectorizeOnlyWhenForced is set, and no #pragma vectorize enable
+; CHECK: remark:
+; CHECK-SAME: loop not vectorized: only vectorizing loops that explicitly request it
+; CHECK: LV: Loop hints prevent vectorization
+
+define dso_local noundef nofpclass(nan inf) double @_Z15CompareDistmatsPKdS0_(ptr noundef readonly captures(none) %distmat1, ptr noundef readonly captures(none) %distmat2) local_unnamed_addr {
+entry:
+  br label %for.body
+
+for.cond.cleanup:                                 ; preds = %for.body
+  %add.lcssa = phi double [ %add, %for.body ]
+  %div = fmul fast double %add.lcssa, 0x3FB1111111111111
+  %0 = tail call fast double @llvm.sqrt.f64(double %div)
+  ret double %0
+
+for.body:                                         ; preds = %entry, %for.body
+  %i.014 = phi i64 [ 0, %entry ], [ %inc, %for.body ]
+  %RMSD.013 = phi double [ 0.000000e+00, %entry ], [ %add, %for.body ]
+  %arrayidx = getelementptr inbounds nuw double, ptr %distmat1, i64 %i.014
+  %1 = load double, ptr %arrayidx, align 8
+  %arrayidx1 = getelementptr inbounds nuw double, ptr %distmat2, i64 %i.014
+  %2 = load double, ptr %arrayidx1, align 8
+  %sub = fsub fast double %1, %2
+  %mul = fmul fast double %sub, %sub
+  %add = fadd fast double %mul, %RMSD.013
+  %inc = add nuw nsw i64 %i.014, 1
+  %exitcond.not = icmp eq i64 %inc, 15
+  br i1 %exitcond.not, label %for.cond.cleanup, label %for.body
+}