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authorGabe Black <gblack@eecs.umich.edu>2007-09-10 11:01:52 -0700
committerGabe Black <gblack@eecs.umich.edu>2007-09-10 11:01:52 -0700
commit8e7bca8b360f973d1c0c8d5e0820a031144ff457 (patch)
tree02471e220c313263ca0f183226135750ec2df5b6 /src/arch/x86/isa/microops/regop.isa
parent3e65e1d0e0dc57831babb6e5a4566bbbc9409acf (diff)
downloadgem5-8e7bca8b360f973d1c0c8d5e0820a031144ff457.tar.xz
X86: Move a comment to be next to the code it describes.
--HG-- extra : convert_revision : c384391175babb7cfdd3885ae9d9f1a9405ea44f
Diffstat (limited to 'src/arch/x86/isa/microops/regop.isa')
-rw-r--r--src/arch/x86/isa/microops/regop.isa10
1 files changed, 5 insertions, 5 deletions
diff --git a/src/arch/x86/isa/microops/regop.isa b/src/arch/x86/isa/microops/regop.isa
index 7ce9dc27f..d2cfff9d4 100644
--- a/src/arch/x86/isa/microops/regop.isa
+++ b/src/arch/x86/isa/microops/regop.isa
@@ -460,6 +460,11 @@ let {{
class Xor(LogicRegOp):
code = 'DestReg = merge(DestReg, psrc1 ^ op2, dataSize)'
+ # Neither of these is quite correct because it assumes that right shifting
+ # a signed or unsigned value does sign or zero extension respectively.
+ # The C standard says that what happens on a right shift with a 1 in the
+ # MSB position is undefined. On x86 and under likely most compilers the
+ # "right thing" happens, but this isn't a guarantee.
class Mul1s(WrRegOp):
code = '''
ProdLow = psrc1 * op2;
@@ -489,11 +494,6 @@ let {{
class Mulel(RdRegOp):
code = 'DestReg = merge(SrcReg1, ProdLow, dataSize);'
- # Neither of these is quite correct because it assumes that right shifting
- # a signed or unsigned value does sign or zero extension respectively.
- # The C standard says that what happens on a right shift with a 1 in the
- # MSB position is undefined. On x86 and under likely most compilers the
- # "right thing" happens, but this isn't a guarantee.
class Muleh(RdRegOp):
def __init__(self, dest, src1=None, flags=None, dataSize="env.dataSize"):
if not src1: