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| author | Senthil Kumar Selvaraj <saaadhu@gcc.gnu.org> | 2023-06-19 12:23:25 +0530 |
|---|---|---|
| committer | Senthil Kumar Selvaraj <saaadhu@gcc.gnu.org> | 2023-06-19 13:51:13 +0530 |
| commit | 58e1bc2b1c8420773b16452d47932a6ca0d003fb (patch) | |
| tree | 0994b2e3f8d41a5914b67d81a74acfe2555f2720 /gcc/config/avr | |
| parent | ccfdda34341423c6034876856cd8ba50f0ca0ef3 (diff) | |
| download | gcc-58e1bc2b1c8420773b16452d47932a6ca0d003fb.zip gcc-58e1bc2b1c8420773b16452d47932a6ca0d003fb.tar.gz gcc-58e1bc2b1c8420773b16452d47932a6ca0d003fb.tar.bz2 | |
avr: Fix wrong array bounds warning on SFR access
The warning was raised on accessing SFRs at addresses below the default
page size, as gcc considers accessing addresses in the first page of
memory as suspicious. This doesn't apply to an embedded target like the
avr, where both flash and RAM have zero as a valid address. Zero is also
a valid address in named address spaces (__memx, flash<n> etc..).
This commit implements TARGET_ADDR_SPACE_ZERO_ADDRESS_VALID for the avr
target and reports to gcc that zero is a valid address on all
address spaces. It also disables flag_delete_null_pointer_checks
based on the target hook, and modifies target-supports.exp to add avr
to the list of targets that always keep null pointer checks. This fixes
a bunch of DejaGNU failures that occur otherwise.
PR target/105523
gcc/ChangeLog:
* common/config/avr/avr-common.cc: Remove setting
of OPT_fdelete_null_pointer_checks.
* config/avr/avr.cc (avr_option_override): Clear
flag_delete_null_pointer_checks if zero_address_valid.
(avr_addr_space_zero_address_valid): New function.
(TARGET_ADDR_SPACE_ZERO_ADDRESS_VALID): Provide target
hook.
gcc/testsuite/ChangeLog:
* lib/target-supports.exp
(check_effective_target_keeps_null_pointer_checks): Add
avr.
* gcc.target/avr/pr105523.c: New test.
Diffstat (limited to 'gcc/config/avr')
| -rw-r--r-- | gcc/config/avr/avr.cc | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/gcc/config/avr/avr.cc b/gcc/config/avr/avr.cc index ef6872a..0447641 100644 --- a/gcc/config/avr/avr.cc +++ b/gcc/config/avr/avr.cc @@ -1095,6 +1095,10 @@ avr_option_override (void) flag_omit_frame_pointer = 0; } + /* Disable flag_delete_null_pointer_checks if zero is a valid address. */ + if (targetm.addr_space.zero_address_valid (ADDR_SPACE_GENERIC)) + flag_delete_null_pointer_checks = 0; + if (flag_pic == 1) warning (OPT_fpic, "%<-fpic%> is not supported"); if (flag_pic == 2) @@ -10501,6 +10505,16 @@ avr_addr_space_diagnose_usage (addr_space_t as, location_t loc) (void) avr_addr_space_supported_p (as, loc); } +/* Implement `TARGET_ADDR_SPACE_ZERO_ADDRESS_VALID. Zero is a valid + address in all address spaces. Even in ADDR_SPACE_FLASH1 etc.., + a zero address is valid and means 0x<RAMPZ val>0000, where RAMPZ is + set to the appropriate segment value. */ + +static bool +avr_addr_space_zero_address_valid (addr_space_t) +{ + return true; +} /* Look if DECL shall be placed in program memory space by means of attribute `progmem' or some address-space qualifier. @@ -15255,6 +15269,9 @@ avr_float_lib_compare_returns_bool (machine_mode mode, enum rtx_code) #undef TARGET_ADDR_SPACE_DIAGNOSE_USAGE #define TARGET_ADDR_SPACE_DIAGNOSE_USAGE avr_addr_space_diagnose_usage +#undef TARGET_ADDR_SPACE_ZERO_ADDRESS_VALID +#define TARGET_ADDR_SPACE_ZERO_ADDRESS_VALID avr_addr_space_zero_address_valid + #undef TARGET_MODE_DEPENDENT_ADDRESS_P #define TARGET_MODE_DEPENDENT_ADDRESS_P avr_mode_dependent_address_p |