X86: Add ext and cc fields to FP microops

Information
Submitter:	Nilay Vaish
Repository:	gem5
Branch:	default
Bugs:
Depends On:
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Description

Changeset 8960:5752699105b1
---------------------------
X86: Add ext and cc fields to FP microops
The cc and ext fields in integer microops hold the flags the microop is
going to read and write respectively. These fields are being provided in
FP microops. Later on this would help in deciding at run time whether or
not certain flags need to be read or written. Currently these are set to 0.

Testing Done

Summary:

-	X86: Add ext field to FP microops
+	X86: Add ext and cc fields to FP microops

Description:

~		Changeset 8955:ee815a899627
	~	Changeset 8960:5752699105b1

~		X86: Add ext field to FP microops
~		The ext field in integer microops holds the flags the microop
~		is going to read and write. This is field is being provided in
~		FP microops. Later on this would help in deciding at run time
~		whether or not certain flag register needs to read or written.
	~	X86: Add ext and cc fields to FP microops
	~	The cc and ext fields in integer microops hold the flags the microop is
	~	going to read and write respectively. These fields are being provided in
	~	FP microops. Later on this would help in deciding at run time whether or
	~	not certain flags need to be read or written. Currently these are set to 0.

Diff:

Revision 2 (+11 -7)

Show changes

	src/arch/x86/insts/microfpop.hh
	src/arch/x86/isa/microops/fpop.isa

The fp microops are pretty underdeveloped, but my impression was that there wasn't a lot of partial updating of the FP condition codes, and that would make this unnecessary. Could you please check how they're updated and report back? If setting the flags are optional but an all or nothing sort of thing, we don't need to add this code.

Nilay Vaish April 21, 2012, 2:32 p.m. (April 21, 2012, 2:32 p.m.)

I think there are two fp microops that read/write the condition codes. Since the CC register
itself is not separate, any check that is introduced on that register, will be in force
even for fp microops. The check that I intend to introduce (it is there is one of the patches
posted on the board), works on the cc bits that would read/written by the microop. Hence, the need
for the change to the fp microops. I think it is possible to keep these changes to only those two
microops. I may try that out once we converge on the final solution for total set of patches.

You have a pending review.

Review Board 2.0.15

This change has been discarded.

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Summary:

Description:

Changeset 8955:ee815a899627

Changeset 8960:5752699105b1

Diff:

Status: Discarded