[NewPassManager] Add tuning option: SLPVectorization [clang-change]

[asbirlea]

Summary

NewPassManager is not using CodeGenOpts values before this patch.
[to be coupled with D61616]

[chandlerc]

Can you update some Clang IR generation test that uses these flags to run w/ the new PM? It should fail without this and pass with this.

LGTM w/ that test updated.

[asbirlea]

Added test. The last RUN line fails before this patch (i.e. the flag to disable vectorization was not used by the new pass manager)

[asbirlea]

Rename new test for clarity.

[chandlerc]

The file name of the test seems odd? How about vectorize-loops.c? I'd also make it a C test and put it in test/CodeGen instead of a C++ test.

test/CodeGenCXX/no-pragma-loop.cpp

7 ↗

(On Diff #198540)

I'd check for an instruction on a vector type as the block labels aren't really that stable.

Should be able to just check for something like:

// CHECK-LABEL: define @vectorize_loop_test {
// CHECK: mul <{{[0-9]+}} x double>

Or something...

Also, you'll want to explicitly pass a target triple here and require that target to be registered so we're not flaky when the host target changes.

[asbirlea]

Updated test.

[chandlerc]

(Sorry for still more comments)

test/CodeGen/loop-vectorize.c

10

You'll want to check that the vector form *doesn't* show up. I would expect this to pass even w/ vectorization enabled due to potential fallback loops.

[asbirlea]

Updated test.
Improvement suggestions are always *very* much welcome!

[chandlerc]

LGTM

[rnk]

test/CodeGen/loop-vectorize.c

2

Please do not use %clang for codegen tests, please only use %clang_cc1.

lib/CodeGen/BackendUtil.cpp

if (PGOOpt.hasValue()) {
       PGOOpt = PGOOptions("",
                           CodeGenOpts.InstrProfileOutput.empty()
                               ? DefaultProfileGenName
                               : CodeGenOpts.InstrProfileOutput,
                           "", PGOOptions::NoAction, PGOOptions::CSIRInstr,
                           CodeGenOpts.DebugInfoForProfiling);
   }
 
-  PassBuilder PB(TM.get(), PipelineTuningOptions(), PGOOpt);
+  PipelineTuningOptions PTO;
+  // For historical reasons, loop interleaving is set to mirror setting for loop
+  // unrolling.
+  PTO.LoopInterleaving = CodeGenOpts.UnrollLoops;
+  PTO.LoopVectorization = CodeGenOpts.VectorizeLoop;
+  PTO.SLPVectorization = CodeGenOpts.VectorizeSLP;
+
+  PassBuilder PB(TM.get(), PTO, PGOOpt);
 
   // Attempt to load pass plugins and register their callbacks with PB.
   for (auto &PluginFN : CodeGenOpts.PassPlugins) {
     auto PassPlugin = PassPlugin::Load(PluginFN);
     if (PassPlugin) {
       PassPlugin->registerPassBuilderCallbacks(PB);
     } else {
       Diags.Report(diag::err_fe_unable_to_load_plugin)

test/CodeGen/loop-vectorize.c

+// RUN: %clang -target x86_64 -S -c -O1 -fvectorize -emit-llvm -o - %s | FileCheck %s -check-prefix=CHECK-ENABLE-VECT
+// RUN: %clang -target x86_64 -S -c -O1 -fno-vectorize -emit-llvm -o - %s | FileCheck %s -check-prefix=CHECK-DISABLE-VECT
+// RUN: %clang -target x86_64 -fexperimental-new-pass-manager -S -c -O1 -fvectorize -emit-llvm -o - %s | FileCheck %s -check-prefix=CHECK-ENABLE-VECT
+// RUN: %clang -target x86_64 -fexperimental-new-pass-manager -S -c -O1 -fno-vectorize -emit-llvm -o - %s | FileCheck %s -check-prefix=CHECK-DISABLE-VECT
+
+// CHECK-ENABLE-VECT-LABEL: @for_test()
+// CHECK-ENABLE-VECT: fmul <{{[0-9]+}} x double>
+
+// CHECK-DISABLE-VECT-LABEL: @for_test()
+// CHECK-DISABLE-VECT: fmul double
+
+#include <stdio.h>
+
+void for_test() {
+  double A[1000], B[1000];
+  int L = 500;
+  for (int i = 0; i < L; i++) {
+    A[i] = i;
+  }
+  for (int i = 0; i < L; i++) {
+    B[i] = A[i]*5;
+  }
+  printf("%lf %lf\n", A[0], B[0]);
+}