diff options
Diffstat (limited to 'gcc/config/sparc/sparc.c')
| -rw-r--r-- | gcc/config/sparc/sparc.c | 49 |
1 files changed, 47 insertions, 2 deletions
diff --git a/gcc/config/sparc/sparc.c b/gcc/config/sparc/sparc.c index 709a92b518e..e880226412e 100644 --- a/gcc/config/sparc/sparc.c +++ b/gcc/config/sparc/sparc.c @@ -5425,7 +5425,7 @@ sparc_return_in_memory (tree type, tree fntype ATTRIBUTE_UNUSED) Return where to find the structure return value address. */ static rtx -sparc_struct_value_rtx (tree fndecl ATTRIBUTE_UNUSED, int incoming) +sparc_struct_value_rtx (tree fndecl, int incoming) { if (TARGET_ARCH64) return 0; @@ -5440,6 +5440,46 @@ sparc_struct_value_rtx (tree fndecl ATTRIBUTE_UNUSED, int incoming) mem = gen_rtx_MEM (Pmode, plus_constant (stack_pointer_rtx, STRUCT_VALUE_OFFSET)); + /* Only follow the SPARC ABI for fixed-size structure returns. + Variable size structure returns are handled per the normal + procedures in GCC. This is enabled by -mstd-struct-return */ + if (incoming == 2 + && sparc_std_struct_return + && TYPE_SIZE_UNIT (TREE_TYPE (fndecl)) + && TREE_CODE (TYPE_SIZE_UNIT (TREE_TYPE (fndecl))) == INTEGER_CST) + { + /* We must check and adjust the return address, as it is + optional as to whether the return object is really + provided. */ + rtx ret_rtx = gen_rtx_REG (Pmode, 31); + rtx scratch = gen_reg_rtx (SImode); + rtx endlab = gen_label_rtx (); + + /* Calculate the return object size */ + tree size = TYPE_SIZE_UNIT (TREE_TYPE (fndecl)); + rtx size_rtx = GEN_INT (TREE_INT_CST_LOW (size) & 0xfff); + /* Construct a temporary return value */ + rtx temp_val = assign_stack_local (Pmode, TREE_INT_CST_LOW (size), 0); + + /* Implement SPARC 32-bit psABI callee returns struck checking + requirements: + + Fetch the instruction where we will return to and see if + it's an unimp instruction (the most significant 10 bits + will be zero). */ + emit_move_insn (scratch, gen_rtx_MEM (SImode, + plus_constant (ret_rtx, 8))); + /* Assume the size is valid and pre-adjust */ + emit_insn (gen_add3_insn (ret_rtx, ret_rtx, GEN_INT (4))); + emit_cmp_and_jump_insns (scratch, size_rtx, EQ, const0_rtx, SImode, 0, endlab); + emit_insn (gen_sub3_insn (ret_rtx, ret_rtx, GEN_INT (4))); + /* Assign stack temp: + Write the address of the memory pointed to by temp_val into + the memory pointed to by mem */ + emit_move_insn (mem, XEXP (temp_val, 0)); + emit_label (endlab); + } + set_mem_alias_set (mem, struct_value_alias_set); return mem; } @@ -6639,9 +6679,14 @@ print_operand (FILE *file, rtx x, int code) so we have to account for it. This insn is used in the 32-bit ABI when calling a function that returns a non zero-sized structure. The 64-bit ABI doesn't have it. Be careful to have this test be the same - as that used on the call. */ + as that used on the call. The exception here is that when + sparc_std_struct_return is enabled, the psABI is followed exactly + and the adjustment is made by the code in sparc_struct_value_rtx. + The call emitted is the same when sparc_std_struct_return is + present. */ if (! TARGET_ARCH64 && current_function_returns_struct + && ! sparc_std_struct_return && (TREE_CODE (DECL_SIZE (DECL_RESULT (current_function_decl))) == INTEGER_CST) && ! integer_zerop (DECL_SIZE (DECL_RESULT (current_function_decl)))) |
