LoopVectorize: Preserve NSW, NUW and IsExact flags.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167174 91177308-0d34-0410-b5e6-96231b3b80d8

8 files changed, 74 insertions, 8 deletions

diff --git a/lib/Transforms/Vectorize/LoopVectorize.cpp b/lib/Transforms/Vectorize/LoopVectorize.cpp
index 94e56a1..c9871e2 100644
--- a/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -849,8 +849,19 @@ SingleBlockLoopVectorizer::vectorizeLoop(LoopVectorizationLegality *Legal) {
         BinaryOperator *BinOp = dyn_cast<BinaryOperator>(Inst);
         Value *A = getVectorValue(Inst->getOperand(0));
         Value *B = getVectorValue(Inst->getOperand(1));
+
         // Use this vector value for all users of the original instruction.
-        WidenMap[Inst] = Builder.CreateBinOp(BinOp->getOpcode(), A, B);
+        Value *V = Builder.CreateBinOp(BinOp->getOpcode(), A, B);
+        WidenMap[Inst] = V;
+
+        // Update the NSW, NUW and Exact flags.
+        BinaryOperator *VecOp = cast<BinaryOperator>(V);
+        if (isa<OverflowingBinaryOperator>(BinOp)) {
+          VecOp->setHasNoSignedWrap(BinOp->hasNoSignedWrap());
+          VecOp->setHasNoUnsignedWrap(BinOp->hasNoUnsignedWrap());
+        }
+        if (isa<PossiblyExactOperator>(VecOp))
+          VecOp->setIsExact(BinOp->isExact());
         break;
       }
       case Instruction::Select: {
diff --git a/test/Transforms/LoopVectorize/X86/gcc-examples.ll b/test/Transforms/LoopVectorize/X86/gcc-examples.ll
index e7a63c9..574c529 100644
--- a/test/Transforms/LoopVectorize/X86/gcc-examples.ll
+++ b/test/Transforms/LoopVectorize/X86/gcc-examples.ll
@@ -10,7 +10,7 @@ target triple = "x86_64-apple-macosx10.8.0"
 ; Select VF = 8;
 ;CHECK: @example1
 ;CHECK: load <8 x i32>
-;CHECK: add <8 x i32>
+;CHECK: add nsw <8 x i32>
 ;CHECK: store <8 x i32>
 ;CHECK: ret void
 define void @example1() nounwind uwtable ssp {
diff --git a/test/Transforms/LoopVectorize/flags.ll b/test/Transforms/LoopVectorize/flags.ll
new file mode 100644
index 0000000..2f22a76
--- /dev/null
+++ b/test/Transforms/LoopVectorize/flags.ll
@@ -0,0 +1,53 @@
+; RUN: opt < %s  -loop-vectorize -force-vector-width=4 -dce -instcombine -licm -S | FileCheck %s
+
+target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
+target triple = "x86_64-apple-macosx10.8.0"
+
+;CHECK: @flags1
+;CHECK: load <4 x i32>
+;CHECK: mul nsw <4 x i32>
+;CHECK: store <4 x i32>
+;CHECK: ret i32
+define i32 @flags1(i32 %n, i32* nocapture %A) nounwind uwtable ssp {
+  %1 = icmp sgt i32 %n, 9
+  br i1 %1, label %.lr.ph, label %._crit_edge
+
+.lr.ph:                                           ; preds = %0, %.lr.ph
+  %indvars.iv = phi i64 [ %indvars.iv.next, %.lr.ph ], [ 9, %0 ]
+  %2 = getelementptr inbounds i32* %A, i64 %indvars.iv
+  %3 = load i32* %2, align 4
+  %4 = mul nsw i32 %3, 3
+  store i32 %4, i32* %2, align 4
+  %indvars.iv.next = add i64 %indvars.iv, 1
+  %lftr.wideiv = trunc i64 %indvars.iv.next to i32
+  %exitcond = icmp eq i32 %lftr.wideiv, %n
+  br i1 %exitcond, label %._crit_edge, label %.lr.ph
+
+._crit_edge:                                      ; preds = %.lr.ph, %0
+  ret i32 undef
+}
+
+
+;CHECK: @flags2
+;CHECK: load <4 x i32>
+;CHECK: mul <4 x i32>
+;CHECK: store <4 x i32>
+;CHECK: ret i32
+define i32 @flags2(i32 %n, i32* nocapture %A) nounwind uwtable ssp {
+  %1 = icmp sgt i32 %n, 9
+  br i1 %1, label %.lr.ph, label %._crit_edge
+
+.lr.ph:                                           ; preds = %0, %.lr.ph
+  %indvars.iv = phi i64 [ %indvars.iv.next, %.lr.ph ], [ 9, %0 ]
+  %2 = getelementptr inbounds i32* %A, i64 %indvars.iv
+  %3 = load i32* %2, align 4
+  %4 = mul i32 %3, 3
+  store i32 %4, i32* %2, align 4
+  %indvars.iv.next = add i64 %indvars.iv, 1
+  %lftr.wideiv = trunc i64 %indvars.iv.next to i32
+  %exitcond = icmp eq i32 %lftr.wideiv, %n
+  br i1 %exitcond, label %._crit_edge, label %.lr.ph
+
+._crit_edge:                                      ; preds = %.lr.ph, %0
+  ret i32 undef
+}
diff --git a/test/Transforms/LoopVectorize/gcc-examples.ll b/test/Transforms/LoopVectorize/gcc-examples.ll
index d8942ac..fce29d2 100644
--- a/test/Transforms/LoopVectorize/gcc-examples.ll
+++ b/test/Transforms/LoopVectorize/gcc-examples.ll
@@ -21,7 +21,7 @@ target triple = "x86_64-apple-macosx10.8.0"
 
 ;CHECK: @example1
 ;CHECK: load <4 x i32>
-;CHECK: add <4 x i32>
+;CHECK: add nsw <4 x i32>
 ;CHECK: store <4 x i32>
 ;CHECK: ret void
 define void @example1() nounwind uwtable ssp {
@@ -227,6 +227,8 @@ define i32 @example9() nounwind uwtable readonly ssp {
 }
 
 ;CHECK: @example10a
+;CHECK: load <4 x i32>
+;CHECK: add nsw <4 x i32>
 ;CHECK: load <4 x i16>
 ;CHECK: add <4 x i16>
 ;CHECK: store <4 x i16>
diff --git a/test/Transforms/LoopVectorize/increment.ll b/test/Transforms/LoopVectorize/increment.ll
index 069b7ea..71ea7689 100644
--- a/test/Transforms/LoopVectorize/increment.ll
+++ b/test/Transforms/LoopVectorize/increment.ll
@@ -11,7 +11,7 @@ target triple = "x86_64-apple-macosx10.8.0"
 ;  }
 ;CHECK: @inc
 ;CHECK: load <4 x i32>
-;CHECK: add <4 x i32>
+;CHECK: add nsw <4 x i32>
 ;CHECK: store <4 x i32>
 ;CHECK: ret void
 define void @inc(i32 %n) nounwind uwtable noinline ssp {
diff --git a/test/Transforms/LoopVectorize/non-const-n.ll b/test/Transforms/LoopVectorize/non-const-n.ll
index 7727b0a..1a6c15e 100644
--- a/test/Transforms/LoopVectorize/non-const-n.ll
+++ b/test/Transforms/LoopVectorize/non-const-n.ll
@@ -11,7 +11,7 @@ target triple = "x86_64-apple-macosx10.8.0"
 ;CHECK: shl i32
 ;CHECK: zext i32
 ;CHECK: load <4 x i32>
-;CHECK: add <4 x i32>
+;CHECK: add nsw <4 x i32>
 ;CHECK: store <4 x i32>
 ;CHECK: ret void
 define void @example1(i32 %n) nounwind uwtable ssp {
diff --git a/test/Transforms/LoopVectorize/reduction.ll b/test/Transforms/LoopVectorize/reduction.ll
index d19f7c1..c1848b3 100644
--- a/test/Transforms/LoopVectorize/reduction.ll
+++ b/test/Transforms/LoopVectorize/reduction.ll
@@ -66,7 +66,7 @@ define i32 @reduction_prod(i32 %n, i32* noalias nocapture %A, i32* noalias nocap
 ;CHECK: @reduction_mix
 ;CHECK: phi <4 x i32>
 ;CHECK: load <4 x i32>
-;CHECK: mul <4 x i32>
+;CHECK: mul nsw <4 x i32>
 ;CHECK: ret i32
 define i32 @reduction_mix(i32 %n, i32* noalias nocapture %A, i32* noalias nocapture %B) nounwind uwtable readonly noinline ssp {
   %1 = icmp sgt i32 %n, 0
diff --git a/test/Transforms/LoopVectorize/start-non-zero.ll b/test/Transforms/LoopVectorize/start-non-zero.ll
index 257df05..5aa3bc0 100644
--- a/test/Transforms/LoopVectorize/start-non-zero.ll
+++ b/test/Transforms/LoopVectorize/start-non-zero.ll
@@ -4,7 +4,7 @@ target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f3
 target triple = "x86_64-apple-macosx10.8.0"
 
 ;CHECK: @start_at_nonzero
-;CHECK: mul <4 x i32>
+;CHECK: mul nuw <4 x i32>
 ;CHECK: ret i32
 define i32 @start_at_nonzero(i32* nocapture %a, i32 %start, i32 %end) nounwind uwtable ssp {
 entry:
@@ -19,7 +19,7 @@ for.body:                                         ; preds = %for.body.lr.ph, %fo
   %indvars.iv = phi i64 [ %0, %for.body.lr.ph ], [ %indvars.iv.next, %for.body ]
   %arrayidx = getelementptr inbounds i32* %a, i64 %indvars.iv
   %1 = load i32* %arrayidx, align 4, !tbaa !0
-  %mul = mul nsw i32 %1, 333
+  %mul = mul nuw i32 %1, 333
   store i32 %mul, i32* %arrayidx, align 4, !tbaa !0
   %indvars.iv.next = add i64 %indvars.iv, 1
   %2 = trunc i64 %indvars.iv.next to i32