Recommit "[Clang] Pragma vectorize_width() implies vectorize(enable)"

This was further discussed at the llvm dev list:

http://lists.llvm.org/pipermail/llvm-dev/2019-October/135602.html

I think the brief summary of that is that this change is an improvement,
this is the behaviour that we expect and promise in ours docs, and also
as a result there are cases where we now emit diagnostics whereas before
pragmas were silently ignored. Two areas where we can improve: 1) the
diagnostic message itself, and 2) and in some cases (e.g. -Os and -Oz)
the vectoriser is (quite understandably) not triggering.

Original commit message:

Specifying the vectorization width was supposed to implicitly enable
vectorization, except that it wasn't really doing this. It was only
setting the vectorize.width metadata, but not vectorize.enable.

This should fix PR27643.

llvm-svn: 374288
This commit is contained in:
Sjoerd Meijer 2019-10-10 08:27:14 +00:00
parent 109c773ab5
commit 80371c74ae
3 changed files with 38 additions and 9 deletions

View File

@ -270,6 +270,14 @@ LoopInfo::createLoopVectorizeMetadata(const LoopAttributes &Attrs,
// Setting vectorize.width
if (Attrs.VectorizeWidth > 0) {
// This implies vectorize.enable = true, but only add it when it is not
// already enabled.
if (Attrs.VectorizeEnable != LoopAttributes::Enable)
Args.push_back(
MDNode::get(Ctx, {MDString::get(Ctx, "llvm.loop.vectorize.enable"),
ConstantAsMetadata::get(ConstantInt::get(
llvm::Type::getInt1Ty(Ctx), 1))}));
Metadata *Vals[] = {
MDString::get(Ctx, "llvm.loop.vectorize.width"),
ConstantAsMetadata::get(ConstantInt::get(llvm::Type::getInt32Ty(Ctx),

View File

@ -58,7 +58,6 @@ void test5(int *List, int Length) {
List[i] = i * 2;
}
// CHECK: ![[LOOP0]] = distinct !{![[LOOP0]], !3}
// CHECK-NEXT: !3 = !{!"llvm.loop.vectorize.enable", i1 true}
@ -70,7 +69,7 @@ void test5(int *List, int Length) {
// CHECK-NEXT: ![[LOOP3]] = distinct !{![[LOOP3]], !5, !3}
// CHECK-NEXT: ![[LOOP4]] = distinct !{![[LOOP4]], !10}
// CHECK-NEXT: ![[LOOP4]] = distinct !{![[LOOP4]], !3, !10}
// CHECK-NEXT: !10 = !{!"llvm.loop.vectorize.width", i32 1}
// CHECK-NEXT: ![[LOOP5]] = distinct !{![[LOOP5]], !10}
// CHECK-NEXT: ![[LOOP5]] = distinct !{![[LOOP5]], !3, !10}

View File

@ -158,23 +158,41 @@ void template_test(double *List, int Length) {
for_template_constant_expression_test<double, 2, 4, 8>(List, Length);
}
void vec_width_1(int *List, int Length) {
// CHECK-LABEL: @{{.*}}vec_width_1{{.*}}(
// CHECK: br label {{.*}}, !llvm.loop ![[LOOP_15:.*]]
#pragma clang loop vectorize(enable) vectorize_width(1)
for (int i = 0; i < Length; i++)
List[i] = i * 2;
}
void width_1(int *List, int Length) {
// CHECK-LABEL: @{{.*}}width_1{{.*}}(
// CHECK: br label {{.*}}, !llvm.loop ![[LOOP_16:.*]]
#pragma clang loop vectorize_width(1)
for (int i = 0; i < Length; i++)
List[i] = i * 2;
}
// CHECK: ![[LOOP_1]] = distinct !{![[LOOP_1]], ![[UNROLL_FULL:.*]]}
// CHECK: ![[UNROLL_FULL]] = !{!"llvm.loop.unroll.full"}
// CHECK: ![[LOOP_2]] = distinct !{![[LOOP_2]], ![[UNROLL_DISABLE:.*]], ![[DISTRIBUTE_DISABLE:.*]], ![[WIDTH_8:.*]], ![[INTERLEAVE_4:.*]]}
// CHECK: ![[LOOP_2]] = distinct !{![[LOOP_2]], ![[UNROLL_DISABLE:.*]], ![[DISTRIBUTE_DISABLE:.*]], ![[VECTORIZE_ENABLE:.*]], ![[WIDTH_8:.*]], ![[INTERLEAVE_4:.*]]}
// CHECK: ![[UNROLL_DISABLE]] = !{!"llvm.loop.unroll.disable"}
// CHECK: ![[DISTRIBUTE_DISABLE]] = !{!"llvm.loop.distribute.enable", i1 false}
// CHECK: ![[VECTORIZE_ENABLE]] = !{!"llvm.loop.vectorize.enable", i1 true}
// CHECK: ![[WIDTH_8]] = !{!"llvm.loop.vectorize.width", i32 8}
// CHECK: ![[INTERLEAVE_4]] = !{!"llvm.loop.interleave.count", i32 4}
// CHECK: ![[LOOP_3]] = distinct !{![[LOOP_3]], ![[INTERLEAVE_4:.*]], ![[INTENABLE_1:.*]], ![[FOLLOWUP_VECTOR_3:.*]]}
// CHECK: ![[INTENABLE_1]] = !{!"llvm.loop.vectorize.enable", i1 true}
// CHECK: ![[LOOP_3]] = distinct !{![[LOOP_3]], ![[INTERLEAVE_4:.*]], ![[VECTORIZE_ENABLE]], ![[FOLLOWUP_VECTOR_3:.*]]}
// CHECK: ![[FOLLOWUP_VECTOR_3]] = !{!"llvm.loop.vectorize.followup_all", ![[AFTER_VECTOR_3:.*]]}
// CHECK: ![[AFTER_VECTOR_3]] = distinct !{![[AFTER_VECTOR_3]], ![[ISVECTORIZED:.*]], ![[UNROLL_8:.*]]}
// CHECK: ![[ISVECTORIZED]] = !{!"llvm.loop.isvectorized"}
// CHECK: ![[UNROLL_8]] = !{!"llvm.loop.unroll.count", i32 8}
// CHECK: ![[LOOP_4]] = distinct !{![[LOOP_4]], ![[WIDTH_2:.*]], ![[INTERLEAVE_2:.*]]}
// CHECK: ![[LOOP_4]] = distinct !{![[LOOP_4]], ![[VECTORIZE_ENABLE]], ![[WIDTH_2:.*]], ![[INTERLEAVE_2:.*]]}
// CHECK: ![[WIDTH_2]] = !{!"llvm.loop.vectorize.width", i32 2}
// CHECK: ![[INTERLEAVE_2]] = !{!"llvm.loop.interleave.count", i32 2}
@ -185,7 +203,7 @@ void template_test(double *List, int Length) {
// CHECK: ![[FOLLOWUP_VECTOR_6]] = !{!"llvm.loop.vectorize.followup_all", ![[AFTER_VECTOR_6:.*]]}
// CHECK: ![[AFTER_VECTOR_6]] = distinct !{![[AFTER_VECTOR_6]], ![[ISVECTORIZED:.*]], ![[UNROLL_8:.*]]}
// CHECK: ![[LOOP_7]] = distinct !{![[LOOP_7]], ![[WIDTH_5:.*]]}
// CHECK: ![[LOOP_7]] = distinct !{![[LOOP_7]], ![[VECTORIZE_ENABLE]], ![[WIDTH_5:.*]]}
// CHECK: ![[WIDTH_5]] = !{!"llvm.loop.vectorize.width", i32 5}
// CHECK: ![[LOOP_8]] = distinct !{![[LOOP_8]], ![[WIDTH_5:.*]]}
@ -213,5 +231,9 @@ void template_test(double *List, int Length) {
// CHECK: ![[AFTER_VECTOR_13]] = distinct !{![[AFTER_VECTOR_13]], ![[ISVECTORIZED:.*]], ![[UNROLL_32:.*]]}
// CHECK: ![[UNROLL_32]] = !{!"llvm.loop.unroll.count", i32 32}
// CHECK: ![[LOOP_14]] = distinct !{![[LOOP_14]], ![[WIDTH_10:.*]]}
// CHECK: ![[LOOP_14]] = distinct !{![[LOOP_14]], ![[VECTORIZE_ENABLE]], ![[WIDTH_10:.*]]}
// CHECK: ![[WIDTH_10]] = !{!"llvm.loop.vectorize.width", i32 10}
// CHECK: ![[LOOP_15]] = distinct !{![[LOOP_15]], ![[WIDTH_1]], ![[VECTORIZE_ENABLE]]}
// CHECK-NEXT: ![[LOOP_16]] = distinct !{![[LOOP_16]], ![[VECTORIZE_ENABLE]], ![[WIDTH_1]]}