From: Paul Mackerras <paulus@ozlabs.org>
To: linuxppc-dev@ozlabs.org
Subject: [PATCH v3 08/17] powerpc: Add emulation for the addpcis instruction
Date: Wed, 30 Aug 2017 14:12:31 +1000 [thread overview]
Message-ID: <1504066360-30128-9-git-send-email-paulus@ozlabs.org> (raw)
In-Reply-To: <1504066360-30128-1-git-send-email-paulus@ozlabs.org>
The addpcis instruction puts the sum of the next instruction address
plus a constant into a register. Since the result depends on the
address of the instruction, it will give an incorrect result if it
is single-stepped out of line, which is what the *probes subsystem
will currently do if a probe is placed on an addpcis instruction.
This fixes the problem by adding emulation of it to analyse_instr().
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
---
arch/powerpc/lib/sstep.c | 14 +++++++++++---
1 file changed, 11 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c
index 114e597..ed2bc4c 100644
--- a/arch/powerpc/lib/sstep.c
+++ b/arch/powerpc/lib/sstep.c
@@ -1021,9 +1021,6 @@ int analyse_instr(struct instruction_op *op, const struct pt_regs *regs,
op->ccval = (regs->ccr & ~(1UL << (31 - rd))) |
(val << (31 - rd));
return 1;
- default:
- op->type = UNKNOWN;
- return 0;
}
break;
case 31:
@@ -1123,6 +1120,17 @@ int analyse_instr(struct instruction_op *op, const struct pt_regs *regs,
op->val = imm;
goto compute_done;
+ case 19:
+ if (((instr >> 1) & 0x1f) == 2) {
+ /* addpcis */
+ imm = (short) (instr & 0xffc1); /* d0 + d2 fields */
+ imm |= (instr >> 15) & 0x3e; /* d1 field */
+ op->val = regs->nip + (imm << 16) + 4;
+ goto compute_done;
+ }
+ op->type = UNKNOWN;
+ return 0;
+
case 20: /* rlwimi */
mb = (instr >> 6) & 0x1f;
me = (instr >> 1) & 0x1f;
--
2.7.4
next prev parent reply other threads:[~2017-08-30 4:12 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-08-30 4:12 [PATCH v3 00/17] powerpc: Do alignment fixups using analyse_instr etc Paul Mackerras
2017-08-30 4:12 ` [PATCH v3 01/17] powerpc: Correct instruction code for xxlor instruction Paul Mackerras
2017-09-01 13:29 ` [v3, " Michael Ellerman
2017-08-30 4:12 ` [PATCH v3 02/17] powerpc: Change analyse_instr so it doesn't modify *regs Paul Mackerras
2017-08-30 4:12 ` [PATCH v3 03/17] powerpc: Don't check MSR FP/VMX/VSX enable bits in analyse_instr() Paul Mackerras
2017-08-30 4:12 ` [PATCH v3 04/17] powerpc: Handle most loads and stores in instruction emulation code Paul Mackerras
2017-08-30 4:12 ` [PATCH v3 05/17] powerpc/64: Fix update forms of loads and stores to write 64-bit EA Paul Mackerras
2017-08-30 4:12 ` [PATCH v3 06/17] powerpc: Fix emulation of the isel instruction Paul Mackerras
2017-08-30 4:12 ` [PATCH v3 07/17] powerpc: Don't update CR0 in emulation of popcnt, prty, bpermd instructions Paul Mackerras
2017-08-30 4:12 ` Paul Mackerras [this message]
2017-08-30 4:12 ` [PATCH v3 09/17] powerpc: Make load/store emulation use larger memory accesses Paul Mackerras
2017-08-30 4:12 ` [PATCH v3 10/17] powerpc: Emulate FP/vector/VSX loads/stores correctly when regs not live Paul Mackerras
2017-08-30 4:12 ` [PATCH v3 11/17] powerpc: Emulate vector element load/store instructions Paul Mackerras
2017-08-30 4:12 ` [PATCH v3 12/17] powerpc: Emulate load/store floating double pair instructions Paul Mackerras
2017-08-30 4:12 ` [PATCH v3 13/17] powerpc: Emulate the dcbz instruction Paul Mackerras
2017-08-30 4:12 ` [PATCH v3 14/17] powerpc: Set regs->dar if memory access fails in emulate_step() Paul Mackerras
2017-08-30 4:12 ` [PATCH v3 15/17] powerpc: Handle opposite-endian processes in emulation code Paul Mackerras
2017-08-30 4:12 ` [PATCH v3 16/17] powerpc: Separate out load/store emulation into its own function Paul Mackerras
2017-08-30 4:12 ` [PATCH v3 17/17] powerpc: Use instruction emulation infrastructure to handle alignment faults Paul Mackerras
2017-08-30 6:34 ` [PATCH v3 18/17] powerpc: Emulate load/store floating point as integer word instructions Paul Mackerras
2017-08-31 0:49 ` [PATCH v3 00/17] powerpc: Do alignment fixups using analyse_instr etc Michael Neuling
2017-08-31 0:54 ` Michael Neuling
2017-08-31 23:51 ` [PATCH 19/17] powerpc: Wrap register number correctly for string load/store instructions Paul Mackerras
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