diff --git a/gcc/ChangeLog b/gcc/ChangeLog index ad824be9af5cabc1106bb72000a5aac95b7d6ef7..198dee3817b01dd3089191e565aabbad46decfde 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2007-02-05 Richard Sandiford <richard@codesourcery.com> + + * dwarf2out.c (dwarf2out_frame_debug_expr): Record the register + saves in a PARALLEL before the register assignments. + 2007-02-05 Richard Sandiford <richard@codesourcery.com> * doc/tm.texi (DWARF_ALT_FRAME_RETURN_COLUMN): Do not require diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c index 6cbf9d3874d4675c72de813a679b5772ebd33c21..186c979abb55c1a3bed5e572576d01f3621a54f2 100644 --- a/gcc/dwarf2out.c +++ b/gcc/dwarf2out.c @@ -1524,13 +1524,31 @@ dwarf2out_frame_debug_expr (rtx expr, const char *label) { int par_index; int limit = XVECLEN (expr, 0); + rtx elem; + + /* PARALLELs have strict read-modify-write semantics, so we + ought to evaluate every rvalue before changing any lvalue. + It's cumbersome to do that in general, but there's an + easy approximation that is enough for all current users: + handle register saves before register assignments. */ + if (GET_CODE (expr) == PARALLEL) + for (par_index = 0; par_index < limit; par_index++) + { + elem = XVECEXP (expr, 0, par_index); + if (GET_CODE (elem) == SET + && MEM_P (SET_DEST (elem)) + && (RTX_FRAME_RELATED_P (elem) || par_index == 0)) + dwarf2out_frame_debug_expr (elem, label); + } for (par_index = 0; par_index < limit; par_index++) - if (GET_CODE (XVECEXP (expr, 0, par_index)) == SET - && (RTX_FRAME_RELATED_P (XVECEXP (expr, 0, par_index)) - || par_index == 0)) - dwarf2out_frame_debug_expr (XVECEXP (expr, 0, par_index), label); - + { + elem = XVECEXP (expr, 0, par_index); + if (GET_CODE (elem) == SET + && (!MEM_P (SET_DEST (elem)) || GET_CODE (expr) == SEQUENCE) + && (RTX_FRAME_RELATED_P (elem) || par_index == 0)) + dwarf2out_frame_debug_expr (elem, label); + } return; }