From bbf117b20e32ca827ee3b00b019d3a88f39f9cec Mon Sep 17 00:00:00 2001 From: Gabe Black Date: Sun, 9 Aug 2009 01:01:18 -0700 Subject: [PATCH] X86: Don't clobber the original dividend when doing signed divide. --- .../arithmetic/multiply_and_divide.py | 44 ++++++++----------- 1 file changed, 18 insertions(+), 26 deletions(-) diff --git a/src/arch/x86/isa/insts/general_purpose/arithmetic/multiply_and_divide.py b/src/arch/x86/isa/insts/general_purpose/arithmetic/multiply_and_divide.py index dbc803350..47ad1d53c 100644 --- a/src/arch/x86/isa/insts/general_purpose/arithmetic/multiply_and_divide.py +++ b/src/arch/x86/isa/insts/general_purpose/arithmetic/multiply_and_divide.py @@ -388,7 +388,6 @@ def macroop IDIV_B_R sub t2, t2, t4 #Find the sign of the divisor - #FIXME!!! This depends on shifts setting the carry flag correctly. slli t0, reg, 1, flags=(ECF,), dataSize=1 # Negate divisor @@ -397,7 +396,6 @@ def macroop IDIV_B_R mov t3, t3, reg, flags=(nCECF,), dataSize=1 #Find the sign of the dividend - #FIXME!!! This depends on shifts setting the carry flag correctly. slli t0, ah, 1, flags=(ECF,), dataSize=1 # Put the dividend's absolute value into t1 and t2 @@ -440,7 +438,7 @@ divLoopTop: mov t5, t5, t4, (CECF,), dataSize=1 # Check the sign of the divisor - slli t0, t3, 1, flags=(ECF,), dataSize=1 + slli t0, reg, 1, flags=(ECF,), dataSize=1 # Negate the (possibly already negated) quotient sub t4, t0, t5, dataSize=1 @@ -458,19 +456,17 @@ def macroop IDIV_B_M sub t2, t0, ah, dataSize=1 sub t2, t2, t4 - ld t3, seg, sib, disp + ld t8, seg, sib, disp #Find the sign of the divisor - #FIXME!!! This depends on shifts setting the carry flag correctly. slli t0, t3, 1, flags=(ECF,), dataSize=1 # Negate divisor - sub t4, t0, t3, dataSize=1 + sub t3, t0, t8, dataSize=1 # Put the divisor's absolute value into t3 - mov t3, t3, t4, flags=(CECF,), dataSize=1 + mov t3, t3, t8, flags=(nCECF,), dataSize=1 #Find the sign of the dividend - #FIXME!!! This depends on shifts setting the carry flag correctly. slli t0, ah, 1, flags=(ECF,), dataSize=1 # Put the dividend's absolute value into t1 and t2 @@ -513,7 +509,7 @@ divLoopTop: mov t5, t5, t4, (CECF,), dataSize=1 # Check the sign of the divisor - slli t0, t3, 1, flags=(ECF,), dataSize=1 + slli t0, t8, 1, flags=(ECF,), dataSize=1 # Negate the (possibly already negated) quotient sub t4, t0, t5, dataSize=1 @@ -532,19 +528,17 @@ def macroop IDIV_B_P sub t2, t2, t4 rdip t7 - ld t3, seg, riprel, disp + ld t8, seg, riprel, disp #Find the sign of the divisor - #FIXME!!! This depends on shifts setting the carry flag correctly. slli t0, t3, 1, flags=(ECF,), dataSize=1 # Negate divisor - sub t4, t0, t3, dataSize=1 + sub t3, t0, t8, dataSize=1 # Put the divisor's absolute value into t3 - mov t3, t3, t4, flags=(CECF,), dataSize=1 + mov t3, t3, t8, flags=(nCECF,), dataSize=1 #Find the sign of the dividend - #FIXME!!! This depends on shifts setting the carry flag correctly. slli t0, ah, 1, flags=(ECF,), dataSize=1 # Put the dividend's absolute value into t1 and t2 @@ -587,7 +581,7 @@ divLoopTop: mov t5, t5, t4, (CECF,), dataSize=1 # Check the sign of the divisor - slli t0, t3, 1, flags=(ECF,), dataSize=1 + slli t0, t8, 1, flags=(ECF,), dataSize=1 # Negate the (possibly already negated) quotient sub t4, t0, t5, dataSize=1 @@ -610,7 +604,6 @@ def macroop IDIV_R sub t2, t2, t4 #Find the sign of the divisor - #FIXME!!! This depends on shifts setting the carry flag correctly. slli t0, reg, 1, flags=(ECF,) # Negate divisor @@ -619,7 +612,6 @@ def macroop IDIV_R mov t3, t3, reg, flags=(nCECF,) #Find the sign of the dividend - #FIXME!!! This depends on shifts setting the carry flag correctly. slli t0, rdx, 1, flags=(ECF,) # Put the dividend's absolute value into t1 and t2 @@ -664,7 +656,7 @@ divLoopTop: mov t5, t5, t4, (CECF,) # Check the sign of the divisor - slli t0, t3, 1, flags=(ECF,) + slli t0, reg, 1, flags=(ECF,) # Negate the (possibly already negated) quotient sub t4, t0, t5 @@ -682,16 +674,16 @@ def macroop IDIV_M sub t2, t0, rdx sub t2, t2, t4 - ld t3, seg, sib, disp + ld t8, seg, sib, disp #Find the sign of the divisor #FIXME!!! This depends on shifts setting the carry flag correctly. slli t0, t3, 1, flags=(ECF,) # Negate divisor - sub t4, t0, t3 + sub t3, t0, t8 # Put the divisor's absolute value into t3 - mov t3, t3, t4, flags=(CECF,) + mov t3, t3, t8, flags=(nCECF,) #Find the sign of the dividend #FIXME!!! This depends on shifts setting the carry flag correctly. @@ -739,7 +731,7 @@ divLoopTop: mov t5, t5, t4, (CECF,) # Check the sign of the divisor - slli t0, t3, 1, flags=(ECF,) + slli t0, t8, 1, flags=(ECF,) # Negate the (possibly already negated) quotient sub t4, t0, t5 @@ -758,16 +750,16 @@ def macroop IDIV_P sub t2, t2, t4 rdip t7 - ld t3, seg, riprel, disp + ld t8, seg, riprel, disp #Find the sign of the divisor #FIXME!!! This depends on shifts setting the carry flag correctly. slli t0, t3, 1, flags=(ECF,) # Negate divisor - sub t4, t0, t3 + sub t3, t0, t8 # Put the divisor's absolute value into t3 - mov t3, t3, t4, flags=(CECF,) + mov t3, t3, t4, flags=(nCECF,) #Find the sign of the dividend #FIXME!!! This depends on shifts setting the carry flag correctly. @@ -815,7 +807,7 @@ divLoopTop: mov t5, t5, t4, (CECF,) # Check the sign of the divisor - slli t0, t3, 1, flags=(ECF,) + slli t0, t8, 1, flags=(ECF,) # Negate the (possibly already negated) quotient sub t4, t0, t5