motorhead/qemu
1
0
Fork 0
mirror of https://github.com/Motorhead1991/qemu.git synced 2025-08-04 00:03:54 -06:00
Code Issues Projects Releases Packages Wiki Activity Actions

target/arm: Set FPCCR.S when executing M-profile floating point insns

Browse source 
The M-profile FPCCR.S bit indicates the security status of
the floating point context. In the pseudocode ExecuteFPCheck()
function it is unconditionally set to match the current
security state whenever a floating point instruction is
executed.

Implement this by adding a new TB flag which tracks whether
FPCCR.S is different from the current security state, so
that we only need to emit the code to update it in the
less-common case when it is not already set correctly.

Note that we will add the handling for the other work done
by ExecuteFPCheck() in later commits.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20190416125744.27770-19-peter.maydell@linaro.org
This commit is contained in:
Peter Maydell 2019-04-29 17:36:01 +01:00
parent ea7ac69d12
commit 6d60c67a1a
4 changed files with 28 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

5
target/arm/helper.c
View file

@ -13417,6 +13417,11 @@ void cpu_get_tb_cpu_state(CPUARMState *env, target_ulong *pc,
flags = FIELD_DP32(flags, TBFLAG_A32, STACKCHECK, 1);
}
if (arm_feature(env, ARM_FEATURE_M_SECURITY) &&
FIELD_EX32(env->v7m.fpccr[M_REG_S], V7M_FPCCR, S) != env->v7m.secure) {
flags = FIELD_DP32(flags, TBFLAG_A32, FPCCR_S_WRONG, 1);
}
*pflags = flags;
*cs_base = 0;
}