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[Qemu-arm] [PATCH 0/3] target-arm: Fix IL in syndromes for FP and copro

From: Peter Maydell
Subject: [Qemu-arm] [PATCH 0/3] target-arm: Fix IL in syndromes for FP and copro traps
Date: Fri, 5 Feb 2016 14:37:44 +0000

This series corrects a bug I noticed while reading the code.

In syndrome register values, the IL bit indicates the instruction
length, and is 1 for 4-byte instructions and 0 for 2-byte
instructions.  All A64 and A32 instructions are 4-byte, but Thumb
instructions may be either 2 or 4 bytes long.  Unfortunately we named
the parameter to the syn_* functions for constructing syndromes
"is_thumb", which falsely implies that it should be set for all Thumb
instructions, rather than only the 16-bit ones.

Fix the parameter names to a less confusing "is_16bit", and
correct the places where we should be passing in 'false' rather
than 's->thumb' for syndrome construction, which are the
coprocessor, VFP and Neon instruction traps (all these are always
32-bit for Thumb).

The calls to syn_aa32_svc() and syn_aa32_bkpt() correctly still
use s->thumb, because for SVC and BKPT the Thumb encoding is 16
bits but the ARM encoding is 32 bits.

Peter Maydell (3):
  target-arm: Correct misleading 'is_thumb' syn_* parameter names
  target-arm: Fix IL bit reported for Thumb coprocessor traps
  target-arm: Fix IL bit reported for Thumb VFP and Neon traps

 target-arm/internals.h | 28 ++++++++++++++--------------
 target-arm/translate.c | 14 +++++++-------
 2 files changed, 21 insertions(+), 21 deletions(-)


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