LoopVectorize: getConsecutiveVector must respect signed arithmetic

We were passing an i32 to ConstantInt::get where an i64 was needed and we must
also pass the sign if we pass negatives numbers. The start index passed to
getConsecutiveVector must also be signed.

Should fix PR15882.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181286 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 79 insertions, 0 deletions

diff --git a/test/Transforms/LoopVectorize/reverse_induction.ll b/test/Transforms/LoopVectorize/reverse_induction.ll
new file mode 100644
index 0000000..f43f02b
--- /dev/null
+++ b/test/Transforms/LoopVectorize/reverse_induction.ll
@@ -0,0 +1,79 @@
+; RUN: opt < %s -loop-vectorize -force-vector-unroll=2 -force-vector-width=4 -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"
+
+; Make sure consecutive vector generates correct negative indices.
+; PR15882
+
+; CHECK: reverse_induction_i64
+; CHECK: add <4 x i64> %[[SPLAT:.*]], <i64 0, i64 -1, i64 -2, i64 -3>
+; CHECK: add <4 x i64> %[[SPLAT]], <i64 -4, i64 -5, i64 -6, i64 -7>
+
+define i32 @reverse_induction_i64(i64 %startval, i32 * %ptr) {
+entry:
+  br label %for.body
+
+for.body:
+  %add.i7 = phi i64 [ %startval, %entry ], [ %add.i, %for.body ]
+  %i.06 = phi i32 [ 0, %entry ], [ %inc4, %for.body ]
+  %redux5 = phi i32 [ 0, %entry ], [ %inc.redux, %for.body ]
+  %add.i = add i64 %add.i7, -1
+  %kind_.i = getelementptr inbounds i32* %ptr, i64 %add.i
+  %tmp.i1 = load i32* %kind_.i, align 4
+  %inc.redux = add i32 %tmp.i1, %redux5
+  %inc4 = add i32 %i.06, 1
+  %exitcond = icmp ne i32 %inc4, 1024
+  br i1 %exitcond, label %for.body, label %loopend
+
+loopend:
+  ret i32 %inc.redux
+}
+
+; CHECK: reverse_induction_i128
+; CHECK: add <4 x i128> %[[SPLAT:.*]], <i128 0, i128 -1, i128 -2, i128 -3>
+; CHECK: add <4 x i128> %[[SPLAT]], <i128 -4, i128 -5, i128 -6, i128 -7>
+define i32 @reverse_induction_i128(i128 %startval, i32 * %ptr) {
+entry:
+  br label %for.body
+
+for.body:
+  %add.i7 = phi i128 [ %startval, %entry ], [ %add.i, %for.body ]
+  %i.06 = phi i32 [ 0, %entry ], [ %inc4, %for.body ]
+  %redux5 = phi i32 [ 0, %entry ], [ %inc.redux, %for.body ]
+  %add.i = add i128 %add.i7, -1
+  %kind_.i = getelementptr inbounds i32* %ptr, i128 %add.i
+  %tmp.i1 = load i32* %kind_.i, align 4
+  %inc.redux = add i32 %tmp.i1, %redux5
+  %inc4 = add i32 %i.06, 1
+  %exitcond = icmp ne i32 %inc4, 1024
+  br i1 %exitcond, label %for.body, label %loopend
+
+loopend:
+  ret i32 %inc.redux
+}
+
+; CHECK: reverse_induction_i16
+; CHECK: add <4 x i16> %[[SPLAT:.*]], <i16 0, i16 -1, i16 -2, i16 -3>
+; CHECK: add <4 x i16> %[[SPLAT]], <i16 -4, i16 -5, i16 -6, i16 -7>
+
+define i32 @reverse_induction_i16(i16 %startval, i32 * %ptr) {
+entry:
+  br label %for.body
+
+for.body:
+  %add.i7 = phi i16 [ %startval, %entry ], [ %add.i, %for.body ]
+  %i.06 = phi i32 [ 0, %entry ], [ %inc4, %for.body ]
+  %redux5 = phi i32 [ 0, %entry ], [ %inc.redux, %for.body ]
+  %add.i = add i16 %add.i7, -1
+  %kind_.i = getelementptr inbounds i32* %ptr, i16 %add.i
+  %tmp.i1 = load i32* %kind_.i, align 4
+  %inc.redux = add i32 %tmp.i1, %redux5
+  %inc4 = add i32 %i.06, 1
+  %exitcond = icmp ne i32 %inc4, 1024
+  br i1 %exitcond, label %for.body, label %loopend
+
+loopend:
+  ret i32 %inc.redux
+}
+
+