[PATCH] D63396: [WinEH] Allocate space in funclets stack to save XMM CSRs

[Reid Kleckner via Phabricator via llvm-commits]

rnk added a comment.

This broke this C++ code:

  int getcsr();
  void usecsrs(double, int, int, int, int, int, int, int, int);
  double getxmm();
  struct HasDtor {
    int x = 42;
    ~HasDtor();
  };
  int foo() {
    int v1 = getcsr();
    int v2 = getcsr();
    int v3 = getcsr();
    int v4 = getcsr();
    int v5 = getcsr();
    int v6 = getcsr();
    int v7 = getcsr();
    int v8 = getcsr();
    double f1 = getxmm();
    HasDtor o;
    usecsrs(f1, v1, v2, v3, v4, v5, v6, v7, v8);
    usecsrs(f1, v1, v2, v3, v4, v5, v6, v7, v8);
    usecsrs(f1, v1, v2, v3, v4, v5, v6, v7, v8);
    usecsrs(f1, v1, v2, v3, v4, v5, v6, v7, v8);
    return v1 + v2 + v3 + v4 + v5 + v6 + v7 + v8;
  }

The movaps instruction in the funclet epilogue does not match the prologue:

  $ ninja -j900 clang && clang -S t.cpp  -o - -O1 | grep 'movaps.*rsp\|dtor'
  ninja: no work to do.
          .def     "?dtor$5@?0??foo@@YAHXZ at 4HA";
  "?dtor$5@?0??foo@@YAHXZ at 4HA":
  .seh_proc "?dtor$5@?0??foo@@YAHXZ at 4HA"
          movaps  %xmm6, 64(%rsp)
          movaps  72(%rsp), %xmm6
          .long   "?dtor$5@?0??foo@@YAHXZ at 4HA"@IMGREL # Action

The code crashes in the epilogue.

I fixed a different issue in rL368631 <https://reviews.llvm.org/rL368631>, but I think this time I will revert this.


Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D63396/new/

https://reviews.llvm.org/D63396