diff options
Diffstat (limited to 'gcc/function.c')
| -rw-r--r-- | gcc/function.c | 51 |
1 files changed, 36 insertions, 15 deletions
diff --git a/gcc/function.c b/gcc/function.c index da78d3fe022..1021fc2ecf3 100644 --- a/gcc/function.c +++ b/gcc/function.c @@ -4059,22 +4059,31 @@ expand_function_start (tree subr) { /* Compute the return values into a pseudo reg, which we will copy into the true return register after the cleanups are done. */ - - /* In order to figure out what mode to use for the pseudo, we - figure out what the mode of the eventual return register will - actually be, and use that. */ - rtx hard_reg - = hard_function_value (TREE_TYPE (DECL_RESULT (subr)), - subr, 1); - - /* Structures that are returned in registers are not aggregate_value_p, - so we may see a PARALLEL or a REG. */ - if (REG_P (hard_reg)) - SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg))); + tree return_type = TREE_TYPE (DECL_RESULT (subr)); + if (TYPE_MODE (return_type) != BLKmode + && targetm.calls.return_in_msb (return_type)) + /* expand_function_end will insert the appropriate padding in + this case. Use the return value's natural (unpadded) mode + within the function proper. */ + SET_DECL_RTL (DECL_RESULT (subr), + gen_reg_rtx (TYPE_MODE (return_type))); else { - gcc_assert (GET_CODE (hard_reg) == PARALLEL); - SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg)); + /* In order to figure out what mode to use for the pseudo, we + figure out what the mode of the eventual return register will + actually be, and use that. */ + rtx hard_reg = hard_function_value (return_type, subr, 1); + + /* Structures that are returned in registers are not + aggregate_value_p, so we may see a PARALLEL or a REG. */ + if (REG_P (hard_reg)) + SET_DECL_RTL (DECL_RESULT (subr), + gen_reg_rtx (GET_MODE (hard_reg))); + else + { + gcc_assert (GET_CODE (hard_reg) == PARALLEL); + SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg)); + } } /* Set DECL_REGISTER flag so that expand_function_end will copy the @@ -4368,10 +4377,22 @@ expand_function_end (void) if (GET_MODE (real_decl_rtl) == BLKmode) PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl)); + /* If a non-BLKmode return value should be padded at the least + significant end of the register, shift it left by the appropriate + amount. BLKmode results are handled using the group load/store + machinery. */ + if (TYPE_MODE (TREE_TYPE (decl_result)) != BLKmode + && targetm.calls.return_in_msb (TREE_TYPE (decl_result))) + { + emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl), + REGNO (real_decl_rtl)), + decl_rtl); + shift_return_value (GET_MODE (decl_rtl), true, real_decl_rtl); + } /* If a named return value dumped decl_return to memory, then we may need to re-do the PROMOTE_MODE signed/unsigned extension. */ - if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl)) + else if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl)) { int unsignedp = TYPE_UNSIGNED (TREE_TYPE (decl_result)); |