diff options
Diffstat (limited to 'gcc/function-abi.cc')
| -rw-r--r-- | gcc/function-abi.cc | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/gcc/function-abi.cc b/gcc/function-abi.cc index 4bace9e..eee789a 100644 --- a/gcc/function-abi.cc +++ b/gcc/function-abi.cc @@ -126,6 +126,42 @@ predefined_function_abi::add_full_reg_clobber (unsigned int regno) SET_HARD_REG_BIT (m_mode_clobbers[i], regno); } +/* Return the set of registers that the caller of the recorded functions must + save in order to honor the requirements of CALLER_ABI. */ + +HARD_REG_SET +function_abi_aggregator:: +caller_save_regs (const function_abi &caller_abi) const +{ + HARD_REG_SET result; + CLEAR_HARD_REG_SET (result); + for (unsigned int abi_id = 0; abi_id < NUM_ABI_IDS; ++abi_id) + { + const predefined_function_abi &callee_abi = function_abis[abi_id]; + + /* Skip cases that clearly aren't problematic. */ + if (abi_id == caller_abi.id () + || hard_reg_set_empty_p (m_abi_clobbers[abi_id])) + continue; + + /* Collect the set of registers that can be "more clobbered" by + CALLEE_ABI than by CALLER_ABI. */ + HARD_REG_SET extra_clobbers; + CLEAR_HARD_REG_SET (extra_clobbers); + for (unsigned int i = 0; i < NUM_MACHINE_MODES; ++i) + { + machine_mode mode = (machine_mode) i; + extra_clobbers |= (callee_abi.mode_clobbers (mode) + & ~caller_abi.mode_clobbers (mode)); + } + + /* Restrict it to the set of registers that we actually saw + clobbers for (e.g. taking -fipa-ra into account). */ + result |= (extra_clobbers & m_abi_clobbers[abi_id]); + } + return result; +} + /* Return the set of registers that cannot be used to hold a value of mode MODE across the calls in a region described by ABIS and MASK, where: |