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b660e9eb7a
Fix a host of problems related to adjustment of symbol values and sizes when relaxing for avr. 1. Adjust symbol size first before adjusting symbol value. Otherwise, a symbol whose value just got adjusted to the relaxed address also ends up getting resized. See pr21404-1.s. 2. Reduce symbol sizes only if their span is below an alignment boundary. Otherwise, the size gets decremented once when the actual instruction is relaxed and padding bytes are added, and again when the padding bytes are deleted (if padding ends up being unnecessary). pr21404-2.s addresses that, and this bug is really the root cause of PR21404. 3. Adjust all symbol values before an alignment boundary. Previous code did not adjust symbol values if they fell in the would-be padded area, resulting in incorrect symbol values in some cases (see pr21404-3.s). 4. Increase symbol sizes if alignment directives require so. As pr21404-4.s shows .global nonzero_sym L1: jmp L1 nonzero_sym: nop nop .p2align 2 .size nonzero_sym, .-nonzero_sym The two nops satisfy the 4 byte alignment at assembly time and therefore the size of nonzero_sym is 4. Relaxation shortens the 4 byte jmp to a 2 byte rjmp, and to satisfy 4 byte alignment the code places 2 extra padding bytes after the nops, increasing nonzero_sym's size by 2. This wasn't handled before. If the assembly code does not have any align directives, then the boundary is the section size, and symbol values and sizes == boundary should also get adjusted. To handle that case, add a did_pad variable and use that to determine whether it should use < boundary or <= boundary. Also get rid of reloc_toaddr, which is now redundant. toaddr is now not adjusted to handle the above case - the newly added did_pad variable does the job. pr21404-{5,6,7,8} are the same testcases written for local symbols, as the code handles them slightly differently.
11 lines
204 B
Makefile
11 lines
204 B
Makefile
#name: AVR local symbol size increase for alignment
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#as: -mmcu=avrxmega2 -mlink-relax
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#ld: -mavrxmega2 --relax
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#source: pr21404-8.s
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#nm: -n -S
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#target: avr-*-*
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#...
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00000002 00000006 t nonzero_sym
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#...
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