Brad Bishop | 1932369 | 2019-04-05 15:28:33 -0400 | [diff] [blame^] | 1 | From 93ae9bb7d25a1adbcbab23a9b8493f370a93f0a3 Mon Sep 17 00:00:00 2001 |
Brad Bishop | 6e60e8b | 2018-02-01 10:27:11 -0500 | [diff] [blame] | 2 | From: James Cowgill <james410@cowgill.org.uk> |
| 3 | Date: Mon, 5 Jan 2015 15:17:01 +0000 |
Brad Bishop | 1932369 | 2019-04-05 15:28:33 -0400 | [diff] [blame^] | 4 | Subject: [PATCH] Add support for mips64 abis in mips_retval.c |
Brad Bishop | 6e60e8b | 2018-02-01 10:27:11 -0500 | [diff] [blame] | 5 | |
| 6 | Signed-off-by: James Cowgill <james410@cowgill.org.uk> |
Brad Bishop | a5c52ff | 2018-11-23 10:55:50 +1300 | [diff] [blame] | 7 | Upstream-Status: Pending [from debian] |
| 8 | Signed-off-by: Hongxu Jia <hongxu.jia@windriver.com> |
Brad Bishop | 1932369 | 2019-04-05 15:28:33 -0400 | [diff] [blame^] | 9 | |
Brad Bishop | 6e60e8b | 2018-02-01 10:27:11 -0500 | [diff] [blame] | 10 | --- |
Brad Bishop | 1932369 | 2019-04-05 15:28:33 -0400 | [diff] [blame^] | 11 | backends/mips_retval.c | 104 +++++++++++++++++++++++++++++++++++++---- |
Brad Bishop | 6e60e8b | 2018-02-01 10:27:11 -0500 | [diff] [blame] | 12 | 1 file changed, 94 insertions(+), 10 deletions(-) |
| 13 | |
| 14 | diff --git a/backends/mips_retval.c b/backends/mips_retval.c |
Brad Bishop | 1932369 | 2019-04-05 15:28:33 -0400 | [diff] [blame^] | 15 | index 656cd1f..57487bb 100644 |
Brad Bishop | 6e60e8b | 2018-02-01 10:27:11 -0500 | [diff] [blame] | 16 | --- a/backends/mips_retval.c |
| 17 | +++ b/backends/mips_retval.c |
| 18 | @@ -91,6 +91,8 @@ enum mips_abi find_mips_abi(Elf *elf) |
| 19 | default: |
| 20 | if ((elf_flags & EF_MIPS_ABI2)) |
| 21 | return MIPS_ABI_N32; |
| 22 | + else if ((ehdr->e_ident[EI_CLASS] == ELFCLASS64)) |
| 23 | + return MIPS_ABI_N64; |
| 24 | } |
| 25 | |
| 26 | /* GCC creates a pseudo-section whose name describes the ABI. */ |
| 27 | @@ -195,6 +197,57 @@ static const Dwarf_Op loc_aggregate[] = |
| 28 | }; |
| 29 | #define nloc_aggregate 1 |
| 30 | |
| 31 | +/* Test if a struct member is a float */ |
| 32 | +static int is_float_child(Dwarf_Die *childdie) |
| 33 | +{ |
| 34 | + /* Test if this is actually a struct member */ |
| 35 | + if (dwarf_tag(childdie) != DW_TAG_member) |
| 36 | + return 0; |
| 37 | + |
| 38 | + /* Get type of member */ |
| 39 | + Dwarf_Attribute attr_mem; |
| 40 | + Dwarf_Die child_type_mem; |
| 41 | + Dwarf_Die *child_typedie = |
| 42 | + dwarf_formref_die(dwarf_attr_integrate(childdie, |
| 43 | + DW_AT_type, |
| 44 | + &attr_mem), &child_type_mem); |
| 45 | + |
| 46 | + if (dwarf_tag(child_typedie) != DW_TAG_base_type) |
| 47 | + return 0; |
| 48 | + |
| 49 | + /* Get base subtype */ |
| 50 | + Dwarf_Word encoding; |
| 51 | + if (dwarf_formudata (dwarf_attr_integrate (child_typedie, |
| 52 | + DW_AT_encoding, |
| 53 | + &attr_mem), &encoding) != 0) |
| 54 | + return 0; |
| 55 | + |
| 56 | + return encoding == DW_ATE_float; |
| 57 | +} |
| 58 | + |
| 59 | +/* Returns the number of fpregs which can be returned in the given struct */ |
| 60 | +static int get_struct_fpregs(Dwarf_Die *structtypedie) |
| 61 | +{ |
| 62 | + Dwarf_Die child_mem; |
| 63 | + int fpregs = 0; |
| 64 | + |
| 65 | + /* Get first structure member */ |
| 66 | + if (dwarf_child(structtypedie, &child_mem) != 0) |
| 67 | + return 0; |
| 68 | + |
| 69 | + do |
| 70 | + { |
| 71 | + /* Ensure this register is a float */ |
| 72 | + if (!is_float_child(&child_mem)) |
| 73 | + return 0; |
| 74 | + |
| 75 | + fpregs++; |
| 76 | + } |
| 77 | + while (dwarf_siblingof (&child_mem, &child_mem) == 0); |
| 78 | + |
| 79 | + return fpregs; |
| 80 | +} |
| 81 | + |
| 82 | int |
| 83 | mips_return_value_location (Dwarf_Die *functypedie, const Dwarf_Op **locp) |
| 84 | { |
| 85 | @@ -240,6 +293,7 @@ mips_return_value_location (Dwarf_Die *functypedie, const Dwarf_Op **locp) |
| 86 | tag = dwarf_tag (typedie); |
| 87 | } |
| 88 | |
| 89 | + Dwarf_Word size; |
| 90 | switch (tag) |
| 91 | { |
| 92 | case -1: |
| 93 | @@ -258,8 +312,6 @@ mips_return_value_location (Dwarf_Die *functypedie, const Dwarf_Op **locp) |
| 94 | case DW_TAG_enumeration_type: |
| 95 | case DW_TAG_pointer_type: |
| 96 | case DW_TAG_ptr_to_member_type: |
| 97 | - { |
| 98 | - Dwarf_Word size; |
| 99 | if (dwarf_formudata (dwarf_attr_integrate (typedie, DW_AT_byte_size, |
| 100 | &attr_mem), &size) != 0) |
| 101 | { |
| 102 | @@ -289,7 +341,7 @@ mips_return_value_location (Dwarf_Die *functypedie, const Dwarf_Op **locp) |
| 103 | if (size <= 4*regsize && abi == MIPS_ABI_O32) |
| 104 | return nloc_fpregquad; |
| 105 | |
| 106 | - goto aggregate; |
| 107 | + goto large; |
| 108 | } |
| 109 | } |
| 110 | *locp = ABI_LOC(loc_intreg, regsize); |
| 111 | @@ -298,18 +350,50 @@ mips_return_value_location (Dwarf_Die *functypedie, const Dwarf_Op **locp) |
| 112 | if (size <= 2*regsize) |
| 113 | return nloc_intregpair; |
| 114 | |
| 115 | - /* Else fall through. Shouldn't happen though (at least with gcc) */ |
| 116 | - } |
| 117 | + /* Else pass in memory. Shouldn't happen though (at least with gcc) */ |
| 118 | + goto large; |
| 119 | |
| 120 | case DW_TAG_structure_type: |
| 121 | case DW_TAG_class_type: |
| 122 | case DW_TAG_union_type: |
| 123 | - case DW_TAG_array_type: |
| 124 | - aggregate: |
| 125 | - /* XXX TODO: Can't handle structure return with other ABI's yet :-/ */ |
| 126 | - if ((abi != MIPS_ABI_O32) && (abi != MIPS_ABI_O64)) |
| 127 | - return -2; |
| 128 | + /* Handle special cases for structures <= 128 bytes in newer ABIs */ |
| 129 | + if (abi == MIPS_ABI_EABI32 || abi == MIPS_ABI_EABI64 || |
| 130 | + abi == MIPS_ABI_N32 || abi == MIPS_ABI_N64) |
| 131 | + { |
| 132 | + if (dwarf_aggregate_size (typedie, &size) == 0 && size <= 16) |
| 133 | + { |
| 134 | + /* |
| 135 | + * Special case in N64 / N32 - |
| 136 | + * structures containing only floats are returned in fp regs. |
| 137 | + * Everything else is returned in integer regs. |
| 138 | + */ |
| 139 | + if (tag != DW_TAG_union_type && |
| 140 | + (abi == MIPS_ABI_N32 || abi == MIPS_ABI_N64)) |
| 141 | + { |
| 142 | + int num_fpregs = get_struct_fpregs(typedie); |
| 143 | + if (num_fpregs == 1 || num_fpregs == 2) |
| 144 | + { |
| 145 | + *locp = loc_fpreg; |
| 146 | + if (num_fpregs == 1) |
| 147 | + return nloc_fpreg; |
| 148 | + else |
| 149 | + return nloc_fpregpair; |
| 150 | + } |
| 151 | + } |
| 152 | + |
| 153 | + *locp = loc_intreg; |
| 154 | + if (size <= 8) |
| 155 | + return nloc_intreg; |
| 156 | + else |
| 157 | + return nloc_intregpair; |
| 158 | + } |
| 159 | + } |
| 160 | + |
| 161 | + /* Fallthrough to handle large types */ |
| 162 | |
| 163 | + case DW_TAG_array_type: |
| 164 | + large: |
| 165 | + /* Return large structures in memory */ |
| 166 | *locp = loc_aggregate; |
| 167 | return nloc_aggregate; |
| 168 | } |