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Bugfix eight: incorrect segment count in ELF header.

The generated examples/ex1 is still not right. But it has the second
segment now. Or almost all of it. Final byte is missing for some reason.
This commit is contained in:
Kartik Agaram 2019-07-15 16:39:13 -07:00
parent 9ad8133197
commit 5490993845
2 changed files with 4 additions and 4 deletions
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@ -2619,7 +2619,7 @@ $emit-headers:end:
emit-elf-header: # out : (address buffered-file), segments : (address stream {string, segment-info}), labels : (address stream {string, label-info})
# pseudocode
# *Elf_e_entry = get(labels, "Entry")->address
# *Elf_e_phnum = segments->write / 20 # size of a row
# *Elf_e_phnum = segments->write / 16 # size of a row
# emit-hex-array(out, Elf_header)
#
# . prolog
@ -2645,13 +2645,13 @@ emit-elf-header: # out : (address buffered-file), segments : (address stream {s
8b/copy 1/mod/*+disp8 0/rm32/EAX . . . 0/r32/EAX 8/disp8 . # copy *(EAX+8) to EAX
# . *Elf_e_entry = EAX
89/copy 0/mod/indirect 5/rm32/.disp32 . . 0/r32/EAX Elf_e_entry/disp32 # copy EAX to *Elf_e_entry
# *Elf_e_phnum = segments->write / 0x20
# *Elf_e_phnum = segments->write / 0x10
# . EAX = segments
8b/copy 1/mod/*+disp8 5/rm32/EBP . . . 0/r32/EAX 0xc/disp8 . # copy *(EBP+12) to EAX
# . len/EAX = segments->write
8b/copy 0/mod/indirect 0/rm32/EAX . . . 0/r32/EAX . . # copy *EAX to EAX
# . EAX = len / 0x20 (destroying EDX)
b9/copy-to-ECX 0x20/imm32
# . EAX = len / 0x10 (destroying EDX)
b9/copy-to-ECX 0x10/imm32
31/xor 3/mod/direct 2/rm32/EDX . . . 2/r32/EDX . . # clear EDX
f7 7/subop/idiv 3/mod/direct 1/rm32/ECX . . . . . . # divide EDX:EAX by ECX, storing quotient in EAX and remainder in EDX
# . *Elf_e_phnum = EAX