jyapayne/Nim
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Fix corner case of checked div/mod on x86 (#10406)

Browse source 
Fixes #10377
This commit is contained in:
LemonBoy 2019-01-22 07:33:27 +01:00 • committed by Andreas Rumpf
commit 7a3f382517
1 changed files with 29 additions and 15 deletions
Download patch file Download diff file Expand all files Collapse all files

30
lib/system/arithm.nim
View file

@ -197,25 +197,39 @@ when asmVersion and not defined(gcc) and not defined(llvm_gcc):
proc divInt(a, b: int): int {.compilerProc, asmNoStackFrame.} = proc divInt(a, b: int): int {.compilerProc, asmNoStackFrame.} =
asm """ asm """
test edx, edx
jne L_NOT_ZERO
call `raiseDivByZero`
L_NOT_ZERO:
cmp ecx, 0x80000000
jne L_DO_DIV
cmp edx, -1
jne L_DO_DIV
call `raiseOverflow`
L_DO_DIV:
mov eax, ecx mov eax, ecx
mov ecx, edx mov ecx, edx
xor edx, edx cdq
idiv ecx idiv ecx
jno theEnd
call `raiseOverflow`
theEnd:
ret ret
""" """
proc modInt(a, b: int): int {.compilerProc, asmNoStackFrame.} = proc modInt(a, b: int): int {.compilerProc, asmNoStackFrame.} =
asm """ asm """
test edx, edx
jne L_NOT_ZERO
call `raiseDivByZero`
L_NOT_ZERO:
cmp ecx, 0x80000000
jne L_DO_DIV
cmp edx, -1
jne L_DO_DIV
call `raiseOverflow`
L_DO_DIV:
mov eax, ecx mov eax, ecx
mov ecx, edx mov ecx, edx
xor edx, edx cdq
idiv ecx idiv ecx
jno theEnd
call `raiseOverflow`
theEnd:
mov eax, edx mov eax, edx
ret ret
""" """