[InstCombine] use loop info when running the pass after loop vectorization

This is the follow-up to D144199 and suggestion from D144045.
We make use of loop info explicit via InstCombine pass parameter
rather than semi-arbitrary via caching.

The only InstCombine transform that uses LoopInfo currently is a
GEP fold in visitGEPOfGEP(), so that shows up as a failure in the
dedicated test for the fold as well as several LoopVectorizer tests
that run extra passes.

I don't see any pass manager regression tests that actually check
for pass options, but this is intended to be NFC for the pass
pipeline behavior - we only try to use loop info where it would
have been used before via caching .

Differential Revision: https://reviews.llvm.org/D144274

Author: rotateright

llvm/lib/Passes/PassBuilderPipelines.cpp

@@ -1117,7 +1117,7 @@ void PassBuilder::addVectorPasses(OptimizationLevel Level,
     FPM.addPass(LoopLoadEliminationPass());
   }
   // Cleanup after the loop optimization passes.
-  FPM.addPass(InstCombinePass());
+  FPM.addPass(InstCombinePass(InstCombineOptions().setUseLoopInfo(true)));
 
   if (Level.getSpeedupLevel() > 1 && ExtraVectorizerPasses) {
     ExtraVectorPassManager ExtraPasses;
@@ -1129,7 +1129,8 @@ void PassBuilder::addVectorPasses(OptimizationLevel Level,
     // dead (or speculatable) control flows or more combining opportunities.
     ExtraPasses.addPass(EarlyCSEPass());
     ExtraPasses.addPass(CorrelatedValuePropagationPass());
-    ExtraPasses.addPass(InstCombinePass());
+    ExtraPasses.addPass(
+        InstCombinePass(InstCombineOptions().setUseLoopInfo(true)));
     LoopPassManager LPM;
     LPM.addPass(LICMPass(PTO.LicmMssaOptCap, PTO.LicmMssaNoAccForPromotionCap,
                          /*AllowSpeculation=*/true));
@@ -1203,7 +1204,7 @@ void PassBuilder::addVectorPasses(OptimizationLevel Level,
     // or SimplifyCFG passes scheduled after us, that would cleanup
     // the CFG mess this may created if allowed to modify CFG, so forbid that.
     FPM.addPass(SROAPass(SROAOptions::PreserveCFG));
-    FPM.addPass(InstCombinePass());
+    FPM.addPass(InstCombinePass(InstCombineOptions().setUseLoopInfo(true)));
     FPM.addPass(
         RequireAnalysisPass<OptimizationRemarkEmitterAnalysis, Function>());
     FPM.addPass(createFunctionToLoopPassAdaptor(
@@ -1217,7 +1218,7 @@ void PassBuilder::addVectorPasses(OptimizationLevel Level,
   FPM.addPass(AlignmentFromAssumptionsPass());
 
   if (IsFullLTO)
-    FPM.addPass(InstCombinePass());
+    FPM.addPass(InstCombinePass(InstCombineOptions().setUseLoopInfo(true)));
 }
 
 ModulePassManager

llvm/lib/Transforms/InstCombine/InstructionCombining.cpp

@@ -4651,10 +4651,9 @@ PreservedAnalyses InstCombinePass::run(Function &F,
   auto &ORE = AM.getResult<OptimizationRemarkEmitterAnalysis>(F);
   auto &TTI = AM.getResult<TargetIRAnalysis>(F);
 
-  // TODO: Only use LoopInfo when the option is set. This requires that the
-  //       callers in the pass pipeline explicitly set the option.
-  auto *LI = AM.getCachedResult<LoopAnalysis>(F);
-  if (!LI && Options.UseLoopInfo)
+  // Only use LoopInfo when the option is set by callers.
+  LoopInfo *LI = nullptr;
+  if (Options.UseLoopInfo)
     LI = &AM.getResult<LoopAnalysis>(F);
 
   auto *AA = &AM.getResult<AAManager>(F);

llvm/test/Transforms/InstCombine/constant-fold-gep.ll

@@ -1,5 +1,7 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt < %s -passes='require<loops>,instcombine' -S | FileCheck %s
+; RUN: opt < %s -passes='instcombine' -S | FileCheck %s --check-prefixes=CHECK,NOLOOPINFO
+; RUN: opt < %s -passes='instcombine<use-loop-info>' -S | FileCheck %s --check-prefixes=CHECK,LOOPINFO
+
 target datalayout = "E-p:64:64:64-p1:16:16:16-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64"
 
 ; Constant folding should fix notionally out-of-bounds indices
@@ -158,13 +160,22 @@ define ptr @gep_plus_addr_sub_self(i64 %addr) {
 }
 
 define ptr @gep_plus_addr_sub_self_in_loop() {
-; CHECK-LABEL: @gep_plus_addr_sub_self_in_loop(
-; CHECK-NEXT:    br label [[LOOP:%.*]]
-; CHECK:       loop:
-; CHECK-NEXT:    [[ADDR:%.*]] = call i64 @get.i64()
-; CHECK-NEXT:    [[P2:%.*]] = getelementptr i8, ptr getelementptr (i8, ptr @g, i64 sub (i64 0, i64 ptrtoint (ptr @g to i64))), i64 [[ADDR]]
-; CHECK-NEXT:    call void @use.ptr(ptr [[P2]])
-; CHECK-NEXT:    br label [[LOOP]]
+; NOLOOPINFO-LABEL: @gep_plus_addr_sub_self_in_loop(
+; NOLOOPINFO-NEXT:    br label [[LOOP:%.*]]
+; NOLOOPINFO:       loop:
+; NOLOOPINFO-NEXT:    [[ADDR:%.*]] = call i64 @get.i64()
+; NOLOOPINFO-NEXT:    [[P1:%.*]] = getelementptr i8, ptr @g, i64 [[ADDR]]
+; NOLOOPINFO-NEXT:    [[P2:%.*]] = getelementptr i8, ptr [[P1]], i64 sub (i64 0, i64 ptrtoint (ptr @g to i64))
+; NOLOOPINFO-NEXT:    call void @use.ptr(ptr [[P2]])
+; NOLOOPINFO-NEXT:    br label [[LOOP]]
+;
+; LOOPINFO-LABEL: @gep_plus_addr_sub_self_in_loop(
+; LOOPINFO-NEXT:    br label [[LOOP:%.*]]
+; LOOPINFO:       loop:
+; LOOPINFO-NEXT:    [[ADDR:%.*]] = call i64 @get.i64()
+; LOOPINFO-NEXT:    [[P2:%.*]] = getelementptr i8, ptr getelementptr (i8, ptr @g, i64 sub (i64 0, i64 ptrtoint (ptr @g to i64))), i64 [[ADDR]]
+; LOOPINFO-NEXT:    call void @use.ptr(ptr [[P2]])
+; LOOPINFO-NEXT:    br label [[LOOP]]
 ;
   %p.int = ptrtoint ptr @g to i64
   %p.int.neg = sub i64 0, %p.int

llvm/test/Transforms/LoopVectorize/ARM/mve-reductions.ll

@@ -1,5 +1,5 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt -passes=loop-vectorize,instcombine,simplifycfg -simplifycfg-require-and-preserve-domtree=1 -tail-predication=enabled < %s -S -o - | FileCheck %s
+; RUN: opt -passes='loop-vectorize,instcombine<use-loop-info>,simplifycfg' -simplifycfg-require-and-preserve-domtree=1 -tail-predication=enabled < %s -S -o - | FileCheck %s
 
 target datalayout = "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64"
 target triple = "thumbv8.1m.main-arm-none-eabi"

llvm/test/Transforms/LoopVectorize/X86/x86-interleaved-accesses-masked-group.ll

@@ -1,6 +1,6 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt -mcpu=skx -S -passes=loop-vectorize,instcombine,simplifycfg -simplifycfg-require-and-preserve-domtree=1 -force-vector-width=8 -force-vector-interleave=1 -enable-interleaved-mem-accesses < %s | FileCheck %s -check-prefix=DISABLED_MASKED_STRIDED
-; RUN: opt -mcpu=skx -S -passes=loop-vectorize,instcombine,simplifycfg -simplifycfg-require-and-preserve-domtree=1 -force-vector-width=8 -force-vector-interleave=1 -enable-interleaved-mem-accesses  -enable-masked-interleaved-mem-accesses < %s | FileCheck %s -check-prefix=ENABLED_MASKED_STRIDED
+; RUN: opt -mcpu=skx -S -passes='loop-vectorize,instcombine<use-loop-info>,simplifycfg' -simplifycfg-require-and-preserve-domtree=1 -force-vector-width=8 -force-vector-interleave=1 -enable-interleaved-mem-accesses < %s | FileCheck %s -check-prefix=DISABLED_MASKED_STRIDED
+; RUN: opt -mcpu=skx -S -passes='loop-vectorize,instcombine<use-loop-info>,simplifycfg' -simplifycfg-require-and-preserve-domtree=1 -force-vector-width=8 -force-vector-interleave=1 -enable-interleaved-mem-accesses  -enable-masked-interleaved-mem-accesses < %s | FileCheck %s -check-prefix=ENABLED_MASKED_STRIDED
 
 target datalayout = "e-m:e-p:32:32-f64:32:64-f80:32-n8:16:32-S128"
 target triple = "i386-unknown-linux-gnu"

llvm/test/Transforms/LoopVectorize/X86/x86-interleaved-store-accesses-with-gaps.ll

@@ -1,6 +1,6 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt -mcpu=skx -S -passes='loop-vectorize,instcombine,simplifycfg,loop-mssa(licm)' -force-vector-width=4 -force-vector-interleave=1 -enable-interleaved-mem-accesses -prefer-predicate-over-epilogue=predicate-dont-vectorize < %s | FileCheck %s -check-prefix=DISABLED_MASKED_STRIDED
-; RUN: opt -mcpu=skx -S -passes='loop-vectorize,instcombine,simplifycfg,loop-mssa(licm)' -force-vector-width=4 -force-vector-interleave=1 -enable-interleaved-mem-accesses  -enable-masked-interleaved-mem-accesses -prefer-predicate-over-epilogue=predicate-dont-vectorize < %s | FileCheck %s -check-prefix=ENABLED_MASKED_STRIDED
+; RUN: opt -mcpu=skx -S -passes='loop-vectorize,instcombine<use-loop-info>,simplifycfg,loop-mssa(licm)' -force-vector-width=4 -force-vector-interleave=1 -enable-interleaved-mem-accesses -prefer-predicate-over-epilogue=predicate-dont-vectorize < %s | FileCheck %s -check-prefix=DISABLED_MASKED_STRIDED
+; RUN: opt -mcpu=skx -S -passes='loop-vectorize,instcombine<use-loop-info>,simplifycfg,loop-mssa(licm)' -force-vector-width=4 -force-vector-interleave=1 -enable-interleaved-mem-accesses  -enable-masked-interleaved-mem-accesses -prefer-predicate-over-epilogue=predicate-dont-vectorize < %s | FileCheck %s -check-prefix=ENABLED_MASKED_STRIDED
 
 target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
 target triple = "x86_64-unknown-linux-gnu"

llvm/test/Transforms/LoopVectorize/consecutive-ptr-uniforms.ll

@@ -1,6 +1,6 @@
 ; REQUIRES: asserts
-; RUN: opt -opaque-pointers=0 < %s -passes=loop-vectorize,instcombine -force-vector-width=4 -force-vector-interleave=1 -debug-only=loop-vectorize -disable-output -print-after=instcombine 2>&1 | FileCheck %s
-; RUN: opt -opaque-pointers=0 < %s -passes=loop-vectorize,instcombine -force-vector-width=4 -force-vector-interleave=1 -enable-interleaved-mem-accesses -debug-only=loop-vectorize -disable-output -print-after=instcombine 2>&1 | FileCheck %s --check-prefix=INTER
+; RUN: opt -opaque-pointers=0 < %s -passes='loop-vectorize,instcombine<use-loop-info>' -force-vector-width=4 -force-vector-interleave=1 -debug-only=loop-vectorize -disable-output -print-after=instcombine 2>&1 | FileCheck %s
+; RUN: opt -opaque-pointers=0 < %s -passes='loop-vectorize,instcombine<use-loop-info>' -force-vector-width=4 -force-vector-interleave=1 -enable-interleaved-mem-accesses -debug-only=loop-vectorize -disable-output -print-after=instcombine 2>&1 | FileCheck %s --check-prefix=INTER
 
 target datalayout = "e-m:e-i64:64-i128:128-n32:64-S128"
 

llvm/test/Transforms/LoopVectorize/interleaved-accesses.ll

@@ -1,5 +1,5 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt -opaque-pointers=0 -S -passes=loop-vectorize,instcombine -force-vector-width=4 -force-vector-interleave=1 -enable-interleaved-mem-accesses=true -runtime-memory-check-threshold=24 < %s | FileCheck %s
+; RUN: opt -opaque-pointers=0 -S -passes='loop-vectorize,instcombine<use-loop-info>' -force-vector-width=4 -force-vector-interleave=1 -enable-interleaved-mem-accesses=true -runtime-memory-check-threshold=24 < %s | FileCheck %s
 
 target datalayout = "e-m:e-i64:64-i128:128-n32:64-S128"