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hex0.S: optimize setting some immediate values.

This commit is contained in:
Andrius Štikonas 2022-07-17 13:12:51 +01:00
parent e7bd0b67ab
commit d96dc0e322
1 changed files with 7 additions and 3 deletions
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10
amd64/Development/hex0.S
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@ -98,7 +98,10 @@ loop_options2: # Skip argv[1]
push rdx # allocate stack for fout
mov rdx, rsp # arg2 = &fout
push 0 # arg5 = 0
mov r9, 0x8000000000000003 # arg4 = EFI_FILE_MODE_CREATE| EFI_FILE_MODE_WRITE | EFI_FILE_MODE_READ
push 7 # to get 0x8000000000000003 we set the rightmost 3 bits
pop r9 # and then do right rotation by 1
ror r9, 1 # arg4 = EFI_FILE_MODE_CREATE| EFI_FILE_MODE_WRITE | EFI_FILE_MODE_READ
mov r8, r13 # arg3 = out
mov rcx, r14 # arg1 = rootdir
push rax # allocate shadow stack space for UEFI function
@ -112,7 +115,8 @@ loop_options2: # Skip argv[1]
push rdx # allocate stack for fin
mov rdx, rsp # arg2 = &fin
push 1 # arg5 = EFI_FILE_READ_ONLY
mov r9, 1 # arg4 = EFI_FILE_MODE_READ
push 1 # prepare to set arg4 to EFI_FILE_MODE_READ
pop r9 # arg4 = EFI_FILE_MODE_READ
mov r8, r12 # arg3 = in
mov rcx, r14 # arg1 = rootdir
push rax # allocate shadow stack space for UEFI function
@ -235,7 +239,7 @@ terminate:
call [rcx+16] # fin->close()
mov rcx, r13 # arg1 = fin
call [rcx+16] # fout->close()
abort: # used for debugging only
mov rsp, rbp # restore stack
ret # return to UEFI