in findGCD of multiply expr return the gcd

we used to return 1 instead of the gcd

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205800 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp
index 08de6213e2242a56d78f3a381185550c65165f3a..d6165111dbabf29324b7e5ec949bfec1b71bc33c 100644 (file)
--- a/lib/Analysis/ScalarEvolution.cpp
+++ b/lib/Analysis/ScalarEvolution.cpp
@@ -6962,10 +6962,12 @@ public:
     if (PartialGCD != One)
       return PartialGCD;
 
+    // Failed to find a PartialGCD: set the Remainder to the full expression,
+    // and return the GCD.
     Remainder = Expr;
     const SCEVMulExpr *Mul = dyn_cast<SCEVMulExpr>(GCD);
     if (!Mul)
-      return PartialGCD;
+      return GCD;
 
     // When the GCD is a multiply expression, try to decompose it:
     // this occurs when Step does not divide the Start expression
@@ -6979,7 +6981,7 @@ public:
       }
     }
 
-    return PartialGCD;
+    return GCD;
   }
 
   const SCEV *visitUDivExpr(const SCEVUDivExpr *Expr) {

diff --git a/test/Analysis/Delinearization/gcd_multiply_expr.ll b/test/Analysis/Delinearization/gcd_multiply_expr.ll
new file mode 100644 (file)
index 0000000..f962f6d
--- /dev/null
+++ b/test/Analysis/Delinearization/gcd_multiply_expr.ll
@@ -0,0 +1,153 @@
+; RUN: opt < %s -basicaa -da -analyze -delinearize
+;
+; a, b, c, d, g, h;
+; char *f;
+; static fn1(p1) {
+;   char *e = p1;
+;   for (; d;) {
+;     a = 0;
+;     for (;; ++a)
+;       for (; b; ++b)
+;         c = e[b + a];
+;   }
+; }
+;
+; fn2() {
+;   for (;;)
+;     fn1(&f[g * h]);
+; }
+
+@g = common global i32 0, align 4
+@h = common global i32 0, align 4
+@f = common global i8* null, align 4
+@a = common global i32 0, align 4
+@b = common global i32 0, align 4
+@c = common global i32 0, align 4
+@d = common global i32 0, align 4
+
+define i32 @fn2() {
+entry:
+  %.pr = load i32* @d, align 4
+  %phitmp = icmp eq i32 %.pr, 0
+  br label %for.cond
+
+for.cond:
+  %0 = phi i1 [ true, %for.cond ], [ %phitmp, %entry ]
+  br i1 %0, label %for.cond, label %for.cond2thread-pre-split.preheader.i
+
+for.cond2thread-pre-split.preheader.i:
+  %1 = load i32* @g, align 4
+  %2 = load i32* @h, align 4
+  %mul = mul nsw i32 %2, %1
+  %3 = load i8** @f, align 4
+  %.pr.pre.i = load i32* @b, align 4
+  br label %for.cond2thread-pre-split.i
+
+for.cond2thread-pre-split.i:
+  %.pr.i = phi i32 [ 0, %for.inc5.i ], [ %.pr.pre.i, %for.cond2thread-pre-split.preheader.i ]
+  %storemerge.i = phi i32 [ %inc6.i, %for.inc5.i ], [ 0, %for.cond2thread-pre-split.preheader.i ]
+  store i32 %storemerge.i, i32* @a, align 4
+  %tobool31.i = icmp eq i32 %.pr.i, 0
+  br i1 %tobool31.i, label %for.inc5.i, label %for.body4.preheader.i
+
+for.body4.preheader.i:
+  %4 = icmp slt i32 %.pr.i, -7
+  %add.i = add i32 %storemerge.i, %mul
+  br i1 %4, label %for.body4.i.preheader, label %for.body4.ur.i.preheader
+
+for.body4.i.preheader:
+  %5 = sub i32 -8, %.pr.i
+  %6 = lshr i32 %5, 3
+  %7 = mul i32 %6, 8
+  br label %for.body4.i
+
+for.body4.i:
+  %8 = phi i32 [ %inc.7.i, %for.body4.i ], [ %.pr.i, %for.body4.i.preheader ]
+  %arrayidx.sum1 = add i32 %add.i, %8
+  %arrayidx.i = getelementptr inbounds i8* %3, i32 %arrayidx.sum1
+  %9 = load i8* %arrayidx.i, align 1
+  %conv.i = sext i8 %9 to i32
+  store i32 %conv.i, i32* @c, align 4
+  %inc.i = add nsw i32 %8, 1
+  store i32 %inc.i, i32* @b, align 4
+  %arrayidx.sum2 = add i32 %add.i, %inc.i
+  %arrayidx.1.i = getelementptr inbounds i8* %3, i32 %arrayidx.sum2
+  %10 = load i8* %arrayidx.1.i, align 1
+  %conv.1.i = sext i8 %10 to i32
+  store i32 %conv.1.i, i32* @c, align 4
+  %inc.1.i = add nsw i32 %8, 2
+  store i32 %inc.1.i, i32* @b, align 4
+  %arrayidx.sum3 = add i32 %add.i, %inc.1.i
+  %arrayidx.2.i = getelementptr inbounds i8* %3, i32 %arrayidx.sum3
+  %11 = load i8* %arrayidx.2.i, align 1
+  %conv.2.i = sext i8 %11 to i32
+  store i32 %conv.2.i, i32* @c, align 4
+  %inc.2.i = add nsw i32 %8, 3
+  store i32 %inc.2.i, i32* @b, align 4
+  %arrayidx.sum4 = add i32 %add.i, %inc.2.i
+  %arrayidx.3.i = getelementptr inbounds i8* %3, i32 %arrayidx.sum4
+  %12 = load i8* %arrayidx.3.i, align 1
+  %conv.3.i = sext i8 %12 to i32
+  store i32 %conv.3.i, i32* @c, align 4
+  %inc.3.i = add nsw i32 %8, 4
+  store i32 %inc.3.i, i32* @b, align 4
+  %arrayidx.sum5 = add i32 %add.i, %inc.3.i
+  %arrayidx.4.i = getelementptr inbounds i8* %3, i32 %arrayidx.sum5
+  %13 = load i8* %arrayidx.4.i, align 1
+  %conv.4.i = sext i8 %13 to i32
+  store i32 %conv.4.i, i32* @c, align 4
+  %inc.4.i = add nsw i32 %8, 5
+  store i32 %inc.4.i, i32* @b, align 4
+  %arrayidx.sum6 = add i32 %add.i, %inc.4.i
+  %arrayidx.5.i = getelementptr inbounds i8* %3, i32 %arrayidx.sum6
+  %14 = load i8* %arrayidx.5.i, align 1
+  %conv.5.i = sext i8 %14 to i32
+  store i32 %conv.5.i, i32* @c, align 4
+  %inc.5.i = add nsw i32 %8, 6
+  store i32 %inc.5.i, i32* @b, align 4
+  %arrayidx.sum7 = add i32 %add.i, %inc.5.i
+  %arrayidx.6.i = getelementptr inbounds i8* %3, i32 %arrayidx.sum7
+  %15 = load i8* %arrayidx.6.i, align 1
+  %conv.6.i = sext i8 %15 to i32
+  store i32 %conv.6.i, i32* @c, align 4
+  %inc.6.i = add nsw i32 %8, 7
+  store i32 %inc.6.i, i32* @b, align 4
+  %arrayidx.sum8 = add i32 %add.i, %inc.6.i
+  %arrayidx.7.i = getelementptr inbounds i8* %3, i32 %arrayidx.sum8
+  %16 = load i8* %arrayidx.7.i, align 1
+  %conv.7.i = sext i8 %16 to i32
+  store i32 %conv.7.i, i32* @c, align 4
+  %inc.7.i = add nsw i32 %8, 8
+  store i32 %inc.7.i, i32* @b, align 4
+  %tobool3.7.i = icmp sgt i32 %inc.7.i, -8
+  br i1 %tobool3.7.i, label %for.inc5.loopexit.ur-lcssa.i, label %for.body4.i
+
+for.inc5.loopexit.ur-lcssa.i:
+  %17 = add i32 %.pr.i, 8
+  %18 = add i32 %17, %7
+  %19 = icmp eq i32 %18, 0
+  br i1 %19, label %for.inc5.i, label %for.body4.ur.i.preheader
+
+for.body4.ur.i.preheader:
+  %.ph = phi i32 [ %18, %for.inc5.loopexit.ur-lcssa.i ], [ %.pr.i, %for.body4.preheader.i ]
+  br label %for.body4.ur.i
+
+for.body4.ur.i:
+  %20 = phi i32 [ %inc.ur.i, %for.body4.ur.i ], [ %.ph, %for.body4.ur.i.preheader ]
+  %arrayidx.sum = add i32 %add.i, %20
+  %arrayidx.ur.i = getelementptr inbounds i8* %3, i32 %arrayidx.sum
+  %21 = load i8* %arrayidx.ur.i, align 1
+  %conv.ur.i = sext i8 %21 to i32
+  store i32 %conv.ur.i, i32* @c, align 4
+  %inc.ur.i = add nsw i32 %20, 1
+  store i32 %inc.ur.i, i32* @b, align 4
+  %tobool3.ur.i = icmp eq i32 %inc.ur.i, 0
+  br i1 %tobool3.ur.i, label %for.inc5.i.loopexit, label %for.body4.ur.i
+
+for.inc5.i.loopexit:
+  br label %for.inc5.i
+
+for.inc5.i:
+  %inc6.i = add nsw i32 %storemerge.i, 1
+  br label %for.cond2thread-pre-split.i
+}