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gdb-xml: fix hacks in powerpc register numbering

The powerpc xml files contained a hack--an empty, non-existent
register--for getting the register numbers to line up for
newer (XML-aware) and older (non-XML-aware) GDB.  While this hack worked
in some cases, it didn't work in all cases, notably when the user used
`finish' or `continue': GDB would attempt to read the non-existent
register and QEMU would complain.

This patch fixes things up properly.  Instead of inserting a fake
register, we explicitly declare the floating-point and SPE registers to
start at 71.  This action accomplishes the same thing as the nasty hack,
except that now GDB never tries to fetch the non-existant register 70.

Signed-off-by: Nathan Froyd <froydnj@codesourcery.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
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1 parent 33890b3 commit 22555301adabad6ef2401a7f02bfc2337044ddbd Nathan Froyd committed with aurel32 Jun 4, 2009
Showing with 2 additions and 20 deletions.
  1. +0 −9 gdb-xml/power-core.xml
  2. +1 −1 gdb-xml/power-fpu.xml
  3. +1 −1 gdb-xml/power-spe.xml
  4. +0 −9 gdb-xml/power64-core.xml
View
9 gdb-xml/power-core.xml
@@ -46,13 +46,4 @@
<reg name="lr" bitsize="32" type="code_ptr"/>
<reg name="ctr" bitsize="32" type="uint32"/>
<reg name="xer" bitsize="32" type="uint32"/>
- <!-- HACK: The way the QEMU GDB stub code is currently written requires
- the "integer" registers from the XML file to span the entirety of
- NUM_CORE_REGS that non-XML-aware GDB requires. Otherwise, XML-aware
- GDB thinks that "coprocessor" registers from XML, such as the
- floating-point registers, have register numbers less than
- NUM_CORE_REGS. This can lead to problems. Work around it by using
- an unnamed register as padding; NUM_CORE_REGS on Power is 71 and
- this register is 70. It would be fpscr for non-XML-aware GDB. -->
- <reg name="" bitsize="32" type="uint32"/>
</feature>
View
2 gdb-xml/power-fpu.xml
@@ -7,7 +7,7 @@
<!DOCTYPE feature SYSTEM "gdb-target.dtd">
<feature name="org.gnu.gdb.power.fpu">
- <reg name="f0" bitsize="64" type="ieee_double"/>
+ <reg name="f0" bitsize="64" type="ieee_double" regnum="71"/>
<reg name="f1" bitsize="64" type="ieee_double"/>
<reg name="f2" bitsize="64" type="ieee_double"/>
<reg name="f3" bitsize="64" type="ieee_double"/>
View
2 gdb-xml/power-spe.xml
@@ -7,7 +7,7 @@
<!DOCTYPE feature SYSTEM "gdb-target.dtd">
<feature name="org.gnu.gdb.power.spe">
- <reg name="ev0h" bitsize="32"/>
+ <reg name="ev0h" bitsize="32" regnum="71"/>
<reg name="ev1h" bitsize="32"/>
<reg name="ev2h" bitsize="32"/>
<reg name="ev3h" bitsize="32"/>
View
9 gdb-xml/power64-core.xml
@@ -46,13 +46,4 @@
<reg name="lr" bitsize="64" type="code_ptr"/>
<reg name="ctr" bitsize="64" type="uint64"/>
<reg name="xer" bitsize="32" type="uint32"/>
- <!-- HACK: The way the QEMU GDB stub code is currently written requires
- the "integer" registers from the XML file to span the entirety of
- NUM_CORE_REGS that non-XML-aware GDB requires. Otherwise, XML-aware
- GDB thinks that "coprocessor" registers from XML, such as the
- floating-point registers, have register numbers less than
- NUM_CORE_REGS. This can lead to problems. Work around it by using
- an unnamed register as padding; NUM_CORE_REGS on Power is 71 and
- this register is 70. It would be fpscr for non-XML-aware GDB. -->
- <reg name="" bitsize="32" type="uint32"/>
</feature>

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