BBVectorize: Fix an invalid reference bug

This fixes PR15289. This bug was introduced (recently) in r175215; collecting
all std::vector references for candidate pairs to delete at once is invalid
because subsequent lookups in the owning DenseMap could invalidate the
references.

bugpoint was able to reduce a useful test case. Unfortunately, because whether
or not this asserts depends on memory layout, this test case will sometimes
appear to produce valid output. Nevertheless, running under valgrind will
reveal the error.

llvm-svn: 175397

1 files changed, 98 insertions, 0 deletions

diff --git a/llvm/test/Transforms/BBVectorize/X86/pr15289.ll b/llvm/test/Transforms/BBVectorize/X86/pr15289.ll
new file mode 100644
index 00000000000..07cc5d8b96b
--- /dev/null
+++ b/llvm/test/Transforms/BBVectorize/X86/pr15289.ll
@@ -0,0 +1,98 @@
+; RUN: opt < %s -basicaa -bb-vectorize -disable-output
+; This is a bugpoint-reduced test case. It did not always assert, but does reproduce the bug
+; and running under valgrind (or some similar tool) will catch the error.
+
+target datalayout = "e-p:64:64:64-S128-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f16:16:16-f32:32:32-f64:64:64-f128:128:128-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
+target triple = "x86_64-apple-darwin12.2.0"
+
+%0 = type { [10 x { float, float }], [10 x { float, float }], [10 x { float, float }], [10 x { float, float }], [10 x { float, float }] }
+%1 = type { [10 x [8 x i8]] }
+%2 = type { i64, i64 }
+%3 = type { [10 x i64], i64, i64, i64, i64, i64 }
+%4 = type { i64, i64, i64, i64, i64, i64 }
+%5 = type { [10 x i64] }
+%6 = type { [10 x float], [10 x float], [10 x float], [10 x float] }
+%struct.__st_parameter_dt.1.3.5.7 = type { %struct.__st_parameter_common.0.2.4.6, i64, i64*, i64*, i8*, i8*, i32, i32, i8*, i8*, i32, i32, i8*, [256 x i8], i32*, i64, i8*, i32, i32, i8*, i8*, i32, i32, i8*, i8*, i32, i32, i8*, i8*, i32, [4 x i8] }
+%struct.__st_parameter_common.0.2.4.6 = type { i32, i32, i8*, i32, i32, i8*, i32* }
+
+@cctenso_ = external unnamed_addr global %0, align 32
+@ctenso_ = external unnamed_addr global %1, align 32
+@i_dim_ = external unnamed_addr global %2, align 16
+@itenso1_ = external unnamed_addr global %3, align 32
+@itenso2_ = external unnamed_addr global %4, align 32
+@ltenso_ = external unnamed_addr global %5, align 32
+@rtenso_ = external unnamed_addr global %6, align 32
+@.cst = external unnamed_addr constant [8 x i8], align 8
+@.cst1 = external unnamed_addr constant [3 x i8], align 8
+@.cst2 = external unnamed_addr constant [29 x i8], align 8
+@.cst3 = external unnamed_addr constant [32 x i8], align 64
+
+define void @cart_to_dc2y_(double* noalias nocapture %xx, double* noalias nocapture %yy, double* noalias nocapture %zz, [5 x { double, double }]* noalias nocapture %c2ten) nounwind uwtable {
+entry:
+  %0 = fmul double undef, undef
+  %1 = fmul double undef, undef
+  %2 = fadd double undef, undef
+  %3 = fmul double undef, 0x3FE8B8B76E3E9919
+  %4 = fsub double %0, %1
+  %5 = fsub double -0.000000e+00, undef
+  %6 = fmul double undef, undef
+  %7 = fmul double %4, %6
+  %8 = fmul double undef, 2.000000e+00
+  %9 = fmul double %8, undef
+  %10 = fmul double undef, %9
+  %11 = fmul double %10, undef
+  %12 = fsub double undef, %7
+  %13 = fmul double %3, %12
+  %14 = fmul double %3, undef
+  %15 = getelementptr inbounds [5 x { double, double }]* %c2ten, i64 0, i64 0, i32 0
+  store double %13, double* %15, align 8, !tbaa !0
+  %16 = getelementptr inbounds [5 x { double, double }]* %c2ten, i64 0, i64 0, i32 1
+  %17 = fmul double undef, %8
+  %18 = fmul double %17, undef
+  %19 = fmul double undef, %18
+  %20 = fadd double undef, undef
+  %21 = fmul double %3, %19
+  %22 = fsub double -0.000000e+00, %21
+  %23 = getelementptr inbounds [5 x { double, double }]* %c2ten, i64 0, i64 1, i32 0
+  store double %22, double* %23, align 8, !tbaa !0
+  %24 = getelementptr inbounds [5 x { double, double }]* %c2ten, i64 0, i64 1, i32 1
+  %25 = fmul double undef, 0x3FE42F601A8C6794
+  %26 = fmul double undef, 2.000000e+00
+  %27 = fsub double %26, %0
+  %28 = fmul double %6, undef
+  %29 = fsub double undef, %28
+  %30 = getelementptr inbounds [5 x { double, double }]* %c2ten, i64 0, i64 2, i32 0
+  store double undef, double* %30, align 8, !tbaa !0
+  %31 = getelementptr inbounds [5 x { double, double }]* %c2ten, i64 0, i64 2, i32 1
+  %32 = fmul double undef, %17
+  %33 = fmul double undef, %17
+  %34 = fmul double undef, %32
+  %35 = fmul double undef, %33
+  %36 = fsub double undef, %35
+  %37 = fmul double %3, %34
+  %38 = getelementptr inbounds [5 x { double, double }]* %c2ten, i64 0, i64 3, i32 0
+  store double %37, double* %38, align 8, !tbaa !0
+  %39 = getelementptr inbounds [5 x { double, double }]* %c2ten, i64 0, i64 3, i32 1
+  %40 = fmul double undef, %8
+  %41 = fmul double undef, %40
+  %42 = fmul double undef, %41
+  %43 = fsub double undef, %42
+  %44 = fmul double %3, %43
+  %45 = getelementptr inbounds [5 x { double, double }]* %c2ten, i64 0, i64 4, i32 0
+  store double %13, double* %45, align 8, !tbaa !0
+  %46 = getelementptr inbounds [5 x { double, double }]* %c2ten, i64 0, i64 4, i32 1
+  %47 = fsub double -0.000000e+00, %14
+  store double %47, double* %16, align 8, !tbaa !0
+  store double undef, double* %24, align 8, !tbaa !0
+  store double -0.000000e+00, double* %31, align 8, !tbaa !0
+  store double undef, double* %39, align 8, !tbaa !0
+  store double undef, double* %46, align 8, !tbaa !0
+  ret void
+}
+
+attributes #0 = { nounwind uwtable }
+attributes #1 = { nounwind readnone }
+attributes #2 = { nounwind }
+
+!0 = metadata !{metadata !"alias set 17: real(kind=8)", metadata !1}
+!1 = metadata !{metadata !1}