[PATCH v2] powerpc: sstep.c: Add modsw, moduw instruction emulation

Add modsw and moduw instruction emulation support to analyse_instr.
modsw is an x-form instruction that calculates signed modulo of values
stored in registers. moduw is similar to modsw but it works with
unsigned values.

Changes in v2:
Don't update CR register as the instruction does not touch that
Arrange extended opcode in numerical order

Signed-off-by: PrasannaKumar Muralidharan <redacted>
---
 arch/powerpc/lib/sstep.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c
index 9c78a9c..b0acdbc 100644
--- a/arch/powerpc/lib/sstep.c
+++ b/arch/powerpc/lib/sstep.c

@@ -1128,6 +1128,11 @@ int __kprobes analyse_instr(struct instruction_op *op, struct pt_regs *regs,
 		case 266:	/* add */
 			regs->gpr[rd] = regs->gpr[ra] + regs->gpr[rb];
 			goto arith_done;
+
+		case 267:	/* moduw */
+			regs->gpr[rd] = (unsigned int) regs->gpr[ra] %
+				(unsigned int) regs->gpr[rb];
+			goto instr_done;
 #ifdef __powerpc64__
 		case 457:	/* divdu */
 			regs->gpr[rd] = regs->gpr[ra] / regs->gpr[rb];

@@ -1148,6 +1153,10 @@ int __kprobes analyse_instr(struct instruction_op *op, struct pt_regs *regs,
 				(int) regs->gpr[rb];
 			goto arith_done;
 
+		case 779:	/* modsw */
+			regs->gpr[rd] = (int) regs->gpr[ra] %
+				(int) regs->gpr[rb];
+			goto instr_done;
 
 /*
  * Logical instructions

-- 
2.9.3

On 2016/12/07 11:15PM, PrasannaKumar Muralidharan wrote:

Add modsw and moduw instruction emulation support to analyse_instr.
modsw is an x-form instruction that calculates signed modulo of values
stored in registers. moduw is similar to modsw but it works with
unsigned values.

Changes in v2:
Don't update CR register as the instruction does not touch that
Arrange extended opcode in numerical order

This changelog should come after '---' below so that it doesn't get 
included in the commit message.

Apart from that, for this patch:
Reviewed-by: Naveen N. Rao <redacted>


Thanks!

Hi Naveen,

quoted

Add modsw and moduw instruction emulation support to analyse_instr.
modsw is an x-form instruction that calculates signed modulo of values
stored in registers. moduw is similar to modsw but it works with
unsigned values.

Changes in v2:
Don't update CR register as the instruction does not touch that
Arrange extended opcode in numerical order

This changelog should come after '---' below so that it doesn't get
included in the commit message.

Oh, I see. Should I send the patch again with the above change? If so
should I mark it v3 or just v2?

Apart from that, for this patch:
Reviewed-by: Naveen N. Rao <redacted>

Thanks and regards,
PrasannaKumar

On 2016/12/13 01:06PM, PrasannaKumar Muralidharan wrote:

Hi Naveen,

quoted

quoted

Add modsw and moduw instruction emulation support to analyse_instr.
modsw is an x-form instruction that calculates signed modulo of values
stored in registers. moduw is similar to modsw but it works with
unsigned values.

Changes in v2:
Don't update CR register as the instruction does not touch that
Arrange extended opcode in numerical order

This changelog should come after '---' below so that it doesn't get
included in the commit message.

Oh, I see. Should I send the patch again with the above change? If so
should I mark it v3 or just v2?

Easier for benh/mpe if you do ;)
Be sure to include my reviewed-by tag in your v3.

- Naveen

quoted

Apart from that, for this patch:
Reviewed-by: Naveen N. Rao <redacted>

Thanks and regards,
PrasannaKumar

quoted

Oh, I see. Should I send the patch again with the above change? If so
should I mark it v3 or just v2?

Easier for benh/mpe if you do ;)
Be sure to include my reviewed-by tag in your v3.

Sure. I will send v3.