This is a little bit far, but optimize cases like:

struct a {
  struct c {
    double x;
    int y;
  } x[1];
};

void foo(struct a A) {
}

into:

define void @foo(double %A.coerce0, i32 %A.coerce1) nounwind {
entry:
  %A = alloca %struct.a, align 8                  ; <%struct.a*> [#uses=1]
  %0 = bitcast %struct.a* %A to %struct.c*        ; <%struct.c*> [#uses=2]
  %1 = getelementptr %struct.c* %0, i32 0, i32 0  ; <double*> [#uses=1]
  store double %A.coerce0, double* %1
  %2 = getelementptr %struct.c* %0, i32 0, i32 1  ; <i32*> [#uses=1]
  store i32 %A.coerce1, i32* %2

instead of:

define void @foo(double %A.coerce0, i64 %A.coerce1) nounwind {
entry:
  %A = alloca %struct.a, align 8                  ; <%struct.a*> [#uses=1]
  %0 = bitcast %struct.a* %A to %0*               ; <%0*> [#uses=2]
  %1 = getelementptr %0* %0, i32 0, i32 0         ; <double*> [#uses=1]
  store double %A.coerce0, double* %1
  %2 = getelementptr %0* %0, i32 0, i32 1         ; <i64*> [#uses=1]
  store i64 %A.coerce1, i64* %2

I only do this now because I never want to look at this code again :)
 

llvm-svn: 109738