Recommit r360171: [DAGCombiner] Avoid creating large tokenfactors in visitTokenFactor.

If we hit the limit, we do expand the outstanding tokenfactors.
Otherwise, we might drop nodes with users in the unexpanded
tokenfactors. This fixes the crashes reported by Jordan Rupprecht.

Reviewers: niravd, spatel, craig.topper, rupprecht

Reviewed By: niravd

Differential Revision: https://reviews.llvm.org/D62633

llvm-svn: 362350

1 files changed, 59 insertions, 0 deletions

diff --git a/llvm/test/CodeGen/X86/dagcombine-tokenfactor-limit-crash.ll b/llvm/test/CodeGen/X86/dagcombine-tokenfactor-limit-crash.ll
new file mode 100644
index 00000000000..412eb7126f5
--- /dev/null
+++ b/llvm/test/CodeGen/X86/dagcombine-tokenfactor-limit-crash.ll
@@ -0,0 +1,59 @@
+; RUN: llc %s -combiner-tokenfactor-inline-limit=5 -o - | FileCheck %s
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+%struct.snork = type { i8 }
+%struct.wombat = type { [15 x i32] }
+
+; CHECK:          pushq   %rbx
+; CHECK-NEXT:     andq    $-32, %rsp
+; CHECK-NEXT:     subq    $66144, %rsp            # imm = 0x10260
+; CHECK-NEXT:     .cfi_offset %rbx, -24
+; CHECK-NEXT:     movabsq $-868076584853899022, %rax # imm = 0xF3F3F8F201F2F8F2
+; CHECK-NEXT:     movq    %rax, (%rsp)
+; CHECK-NEXT:     movb    $-13, 8263(%rsp)
+; CHECK-NEXT:     movq    %rdi, %rbx
+; CHECK-NEXT:     callq   hoge
+; CHECK-NEXT:     movq    %rbx, %rdi
+; CHECK-NEXT:     callq   hoge
+; CHECK-NEXT:     callq   hoge
+; CHECK-NEXT:     callq   hoge
+; CHECK-NEXT:     callq   eggs
+; CHECK-NEXT:     callq   hoge
+; CHECK-NEXT:     movq    %rbx, %rax
+; CHECK-NEXT:     leaq    -8(%rbp), %rsp
+; CHECK-NEXT:     popq    %rbx
+; CHECK-NEXT:     popq    %rbp
+; CHECK-NEXT:    .cfi_def_cfa %rsp, 8
+; CHECK-NEXT:    retq
+define void @spam(%struct.snork* noalias sret %arg, %struct.snork* %arg2) {
+bb:
+  %tmp = alloca i8, i64 66112, align 32
+  %tmp7 = ptrtoint i8* %tmp to i64
+  %tmp914 = inttoptr i64 undef to %struct.wombat*
+  %tmp915 = inttoptr i64 undef to %struct.snork*
+  %tmp916 = inttoptr i64 undef to %struct.snork*
+  %tmp917 = inttoptr i64 undef to %struct.wombat*
+  %tmp918 = inttoptr i64 undef to %struct.snork*
+  %tmp921 = inttoptr i64 undef to %struct.snork*
+  %tmp2055 = inttoptr i64 %tmp7 to i64*
+  store i64 -868076584853899022, i64* %tmp2055, align 1
+  %tmp2056 = add i64 %tmp7, 8263
+  %tmp2057 = inttoptr i64 %tmp2056 to i8*
+  store i8 -13, i8* %tmp2057, align 1
+  br label %bb2058
+
+bb2058:                                           ; preds = %bb
+  call void @hoge(%struct.snork* %arg)
+  call void @hoge(%struct.snork* %arg)
+  call void @hoge(%struct.snork* %tmp915)
+  call void @hoge(%struct.snork* %tmp916)
+  call void @eggs(%struct.snork* %tmp918, %struct.wombat* %tmp914, %struct.wombat* %tmp917)
+  call void @hoge(%struct.snork* %tmp921)
+  ret void
+}
+
+declare void @hoge(%struct.snork*)
+
+declare void @eggs(%struct.snork*, %struct.wombat*, %struct.wombat*)