[DA] Simplify runtime predicate collection (#157523)

Removes DependenceInfo::getRuntimeAssumptions(), DependenceInfo::Assumptions,
and the print of "Runtime Assumptions:". The runtime assumptions are still
properly attached to each Dependence result and printed as part of the
per-dependence output.

Author: sebpop

llvm/include/llvm/Analysis/DependenceAnalysis.h

@@ -355,16 +355,11 @@ class DependenceInfo {
 
   Function *getFunction() const { return F; }
 
-  /// getRuntimeAssumptions - Returns all the runtime assumptions under which
-  /// the dependence test is valid.
-  LLVM_ABI SCEVUnionPredicate getRuntimeAssumptions() const;
-
 private:
   AAResults *AA;
   ScalarEvolution *SE;
   LoopInfo *LI;
   Function *F;
-  SmallVector<const SCEVPredicate *, 4> Assumptions;
 
   /// Subscript - This private struct represents a pair of subscripts from
   /// a pair of potentially multi-dimensional array references. We use a

llvm/lib/Analysis/DependenceAnalysis.cpp

@@ -441,11 +441,6 @@ static void dumpExampleDependence(raw_ostream &OS, DependenceInfo *DA,
       }
     }
   }
-  SCEVUnionPredicate Assumptions = DA->getRuntimeAssumptions();
-  if (!Assumptions.isAlwaysTrue()) {
-    OS << "Runtime Assumptions:\n";
-    Assumptions.print(OS, 0);
-  }
 }
 
 void DependenceAnalysisWrapperPass::print(raw_ostream &OS,
@@ -3384,10 +3379,6 @@ bool DependenceInfo::invalidate(Function &F, const PreservedAnalyses &PA,
          Inv.invalidate<LoopAnalysis>(F, PA);
 }
 
-SCEVUnionPredicate DependenceInfo::getRuntimeAssumptions() const {
-  return SCEVUnionPredicate(Assumptions, *SE);
-}
-
 // depends -
 // Returns NULL if there is no dependence.
 // Otherwise, return a Dependence with as many details as possible.
@@ -3488,20 +3479,10 @@ DependenceInfo::depends(Instruction *Src, Instruction *Dst,
                                         SCEVUnionPredicate(Assume, *SE));
   }
 
-  if (!Assume.empty()) {
-    if (!UnderRuntimeAssumptions)
-      return std::make_unique<Dependence>(Src, Dst,
-                                          SCEVUnionPredicate(Assume, *SE));
-    // Add non-redundant assumptions.
-    unsigned N = Assumptions.size();
-    for (const SCEVPredicate *P : Assume) {
-      bool Implied = false;
-      for (unsigned I = 0; I != N && !Implied; I++)
-        if (Assumptions[I]->implies(P, *SE))
-          Implied = true;
-      if (!Implied)
-        Assumptions.push_back(P);
-    }
+  if (!Assume.empty() && !UnderRuntimeAssumptions) {
+    // Runtime assumptions needed but not allowed.
+    return std::make_unique<Dependence>(Src, Dst,
+                                        SCEVUnionPredicate(Assume, *SE));
   }
 
   unsigned Pairs = 1;

llvm/test/Analysis/DependenceAnalysis/DifferentOffsets.ll

@@ -34,8 +34,6 @@ define i32 @alias_with_parametric_offset(ptr nocapture %A, i64 %n) {
 ; CHECK-NEXT:    Equal predicate: (zext i2 (trunc i64 %n to i2) to i64) == 0
 ; CHECK-NEXT:  Src: %0 = load i32, ptr %A, align 1 --> Dst: %0 = load i32, ptr %A, align 1
 ; CHECK-NEXT:    da analyze - none!
-; CHECK-NEXT:  Runtime Assumptions:
-; CHECK-NEXT:  Equal predicate: (zext i2 (trunc i64 %n to i2) to i64) == 0
 ;
 entry:
   %arrayidx = getelementptr inbounds i8, ptr %A, i64 %n
@@ -55,9 +53,6 @@ define i32 @alias_with_parametric_expr(ptr nocapture %A, i64 %n, i64 %m) {
 ; CHECK-NEXT:    Equal predicate: (zext i2 (-2 + (trunc i64 %m to i2)) to i64) == 0
 ; CHECK-NEXT:  Src: %0 = load i32, ptr %arrayidx1, align 1 --> Dst: %0 = load i32, ptr %arrayidx1, align 1
 ; CHECK-NEXT:    da analyze - none!
-; CHECK-NEXT:  Runtime Assumptions:
-; CHECK-NEXT:  Equal predicate: (zext i2 ((trunc i64 %m to i2) + (-2 * (trunc i64 %n to i2))) to i64) == 0
-; CHECK-NEXT:  Equal predicate: (zext i2 (-2 + (trunc i64 %m to i2)) to i64) == 0
 ;
 entry:
   %mul = mul nsw i64 %n, 10
@@ -81,8 +76,6 @@ define i32 @gep_i8_vs_i32(ptr nocapture %A, i64 %n, i64 %m) {
 ; CHECK-NEXT:    Equal predicate: (zext i2 (trunc i64 %n to i2) to i64) == 0
 ; CHECK-NEXT:  Src: store i32 42, ptr %arrayidx1, align 4 --> Dst: store i32 42, ptr %arrayidx1, align 4
 ; CHECK-NEXT:    da analyze - none!
-; CHECK-NEXT:  Runtime Assumptions:
-; CHECK-NEXT:  Equal predicate: (zext i2 (trunc i64 %n to i2) to i64) == 0
 ;
 entry:
   %arrayidx0 = getelementptr inbounds i8, ptr %A, i64 %n

llvm/test/Analysis/DependenceAnalysis/MIVCheckConst.ll

@@ -50,9 +50,6 @@ define void @test(ptr %A, ptr %B, i1 %arg, i32 %n, i32 %m) align 2 {
 ; CHECK-NEXT:    Equal predicate: (8 * (zext i4 (trunc i32 %v1 to i4) to i32))<nuw><nsw> == 0
 ; CHECK-NEXT:  Src: %v32 = load <32 x i32>, ptr %v30, align 128 --> Dst: %v32 = load <32 x i32>, ptr %v30, align 128
 ; CHECK-NEXT:    da analyze - consistent input [0 S S]!
-; CHECK-NEXT:  Runtime Assumptions:
-; CHECK-NEXT:  Equal predicate: (zext i7 (4 * (trunc i32 %v1 to i7) * (1 + (trunc i32 %n to i7))) to i32) == 0
-; CHECK-NEXT:  Equal predicate: (8 * (zext i4 (trunc i32 %v1 to i4) to i32))<nuw><nsw> == 0
 ;
 entry:
   %v1 = load i32, ptr %B, align 4