[SCEV] Support SCEVUMinExpr in getRangeRef.

This patch adds support for SCEVUMinExpr to getRangeRef,
similar to the support for SCEVUMaxExpr.

Reviewers: sanjoy.google, efriedma, reames, nikic

Reviewed By: sanjoy.google

Differential Revision: https://reviews.llvm.org/D67177

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@371768 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp
index 04d4105cb2eb9a28cab5a893b84828a9636da694..3817b1142d36d3fc90bb452e580ea9a9e71f2f9e 100644 (file)
--- a/lib/Analysis/ScalarEvolution.cpp
+++ b/lib/Analysis/ScalarEvolution.cpp
@@ -5596,6 +5596,14 @@ ScalarEvolution::getRangeRef(const SCEV *S,
                     ConservativeResult.intersectWith(X, RangeType));
   }
 
+  if (const SCEVUMinExpr *UMin = dyn_cast<SCEVUMinExpr>(S)) {
+    ConstantRange X = getRangeRef(UMin->getOperand(0), SignHint);
+    for (unsigned i = 1, e = UMin->getNumOperands(); i != e; ++i)
+      X = X.umin(getRangeRef(UMin->getOperand(i), SignHint));
+    return setRange(UMin, SignHint,
+                    ConservativeResult.intersectWith(X, RangeType));
+  }
+
   if (const SCEVUDivExpr *UDiv = dyn_cast<SCEVUDivExpr>(S)) {
     ConstantRange X = getRangeRef(UDiv->getLHS(), SignHint);
     ConstantRange Y = getRangeRef(UDiv->getRHS(), SignHint);

diff --git a/test/Analysis/ScalarEvolution/max-expr-cache.ll b/test/Analysis/ScalarEvolution/max-expr-cache.ll
index e30345eb98402d5386825257ca913ff045d7f5fa..52552bef39985c5d0e580774f83eb4640225d49f 100644 (file)
--- a/test/Analysis/ScalarEvolution/max-expr-cache.ll
+++ b/test/Analysis/ScalarEvolution/max-expr-cache.ll
@@ -130,7 +130,7 @@ bb4:
   %tmp45 = icmp ult i32 %tmp43, 256
   %tmp46 = select i1 %tmp45, i32 %tmp43, i32 256
 ; CHECK:  %tmp46 = select i1 %tmp45, i32 %tmp43, i32 256
-; CHECK-NEXT:  --> (256 umin (1 + (256 umin (1 + (256 umin (1 + (256 umin (1 + (256 umin (1 + (256 umin (1 + (256 umin (1 + (256 umin {%tmp3,+,-256}<%bb4>)) umin {%tmp3,+,-256}<%bb4>)) umin {%tmp3,+,-256}<%bb4>)) umin {%tmp3,+,-256}<%bb4>)) umin {%tmp3,+,-256}<%bb4>)) umin {%tmp3,+,-256}<%bb4>)) umin {%tmp3,+,-256}<%bb4>)) umin {%tmp3,+,-256}<%bb4>) 
+; CHECK-NEXT:  -->  (256 umin (1 + (256 umin (1 + (256 umin (1 + (256 umin (1 + (256 umin (1 + (256 umin (1 + (256 umin (1 + (256 umin {%tmp3,+,-256}<%bb4>))<nuw><nsw> umin {%tmp3,+,-256}<%bb4>))<nuw><nsw> umin {%tmp3,+,-256}<%bb4>))<nuw><nsw> umin {%tmp3,+,-256}<%bb4>))<nuw><nsw> umin {%tmp3,+,-256}<%bb4>))<nuw><nsw> umin {%tmp3,+,-256}<%bb4>))<nuw><nsw> umin {%tmp3,+,-256}<%bb4>))<nuw><nsw> umin {%tmp3,+,-256}<%bb4>) U: [0,257) S: [0,257) Exits: <<Unknown>> LoopDispositions: { %bb4: Computable, %bb53: Invariant }
   %tmp47 = icmp ugt i32 %tmp44, %tmp46
   %tmp48 = select i1 %tmp47, i32 %tmp44, i32 %tmp46
   %tmp49 = ashr i32 %tmp48, 3

diff --git a/test/Analysis/ScalarEvolution/trip-count15.ll b/test/Analysis/ScalarEvolution/trip-count15.ll
index a15e3c66bf4262965844c3e376542f037fb2d1bb..4469439b046e06fe38278359dbbece7eed48b643 100644 (file)
--- a/test/Analysis/ScalarEvolution/trip-count15.ll
+++ b/test/Analysis/ScalarEvolution/trip-count15.ll
@@ -5,15 +5,15 @@ define void @umin_unsigned_check(i64 %n) {
 ; CHECK-LABEL: 'umin_unsigned_check'
 ; CHECK-NEXT:  Classifying expressions for: @umin_unsigned_check
 ; CHECK-NEXT:    %min.n = select i1 %min.cmp, i64 4096, i64 %n
-; CHECK-NEXT:    --> (4096 umin %n) U: full-set S: full-set
+; CHECK-NEXT:    --> (4096 umin %n) U: [0,4097) S: [0,4097)
 ; CHECK-NEXT:    %iv = phi i64 [ 0, %entry ], [ %iv.next, %loop ]
-; CHECK-NEXT:    --> {0,+,1}<%loop> U: full-set S: full-set Exits: <<Unknown>> LoopDispositions: { %loop: Computable }
+; CHECK-NEXT:    --> {0,+,1}<%loop> U: [0,4098) S: [0,4098) Exits: (1 + (4096 umin %n))<nuw><nsw> LoopDispositions: { %loop: Computable }
 ; CHECK-NEXT:    %iv.next = add i64 %iv, 1
-; CHECK-NEXT:    --> {1,+,1}<%loop> U: full-set S: full-set Exits: <<Unknown>> LoopDispositions: { %loop: Computable }
+; CHECK-NEXT:    --> {1,+,1}<%loop> U: [1,4099) S: [1,4099) Exits: (2 + (4096 umin %n)) LoopDispositions: { %loop: Computable }
 ; CHECK-NEXT:  Determining loop execution counts for: @umin_unsigned_check
-; CHECK-NEXT:  Loop %loop: Unpredictable backedge-taken count.
-; CHECK-NEXT:  Loop %loop: Unpredictable max backedge-taken count.
-; CHECK-NEXT:  Loop %loop: Unpredictable predicated backedge-taken count.
+; CHECK-NEXT:  Loop %loop: backedge-taken count is (1 + (4096 umin %n))<nuw><nsw>
+; CHECK-NEXT:  Loop %loop: max backedge-taken count is 4097
+; CHECK-NEXT:  Loop %loop: Predicated backedge-taken count is (1 + (4096 umin %n))<nuw><nsw>
 ;
 entry:
   %min.cmp = icmp ult i64 4096, %n
@@ -33,15 +33,15 @@ define void @umin_signed_check(i64 %n) {
 ; CHECK-LABEL: 'umin_signed_check'
 ; CHECK-NEXT:  Classifying expressions for: @umin_signed_check
 ; CHECK-NEXT:    %min.n = select i1 %min.cmp, i64 4096, i64 %n
-; CHECK-NEXT:    --> (4096 umin %n) U: full-set S: full-set
+; CHECK-NEXT:    --> (4096 umin %n) U: [0,4097) S: [0,4097)
 ; CHECK-NEXT:    %iv = phi i64 [ 0, %entry ], [ %iv.next, %loop ]
-; CHECK-NEXT:    --> {0,+,1}<%loop> U: full-set S: full-set Exits: <<Unknown>> LoopDispositions: { %loop: Computable }
+; CHECK-NEXT:    --> {0,+,1}<%loop> U: [0,4098) S: [0,4098) Exits: (1 + (4096 umin %n))<nuw><nsw> LoopDispositions: { %loop: Computable }
 ; CHECK-NEXT:    %iv.next = add i64 %iv, 1
-; CHECK-NEXT:    --> {1,+,1}<%loop> U: full-set S: full-set Exits: <<Unknown>> LoopDispositions: { %loop: Computable }
+; CHECK-NEXT:    --> {1,+,1}<%loop> U: [1,4099) S: [1,4099) Exits: (2 + (4096 umin %n)) LoopDispositions: { %loop: Computable }
 ; CHECK-NEXT:  Determining loop execution counts for: @umin_signed_check
-; CHECK-NEXT:  Loop %loop: Unpredictable backedge-taken count.
-; CHECK-NEXT:  Loop %loop: Unpredictable max backedge-taken count.
-; CHECK-NEXT:  Loop %loop: Unpredictable predicated backedge-taken count.
+; CHECK-NEXT:  Loop %loop: backedge-taken count is (1 + (4096 umin %n))<nuw><nsw>
+; CHECK-NEXT:  Loop %loop: max backedge-taken count is 4097
+; CHECK-NEXT:  Loop %loop: Predicated backedge-taken count is (1 + (4096 umin %n))<nuw><nsw>
 ;
 entry:
   %min.cmp = icmp ult i64 4096, %n