target/arm: Fix handling of cortex-m FTYPE flag in EXCRET

According to the PushStack() pseudocode in the armv7m RM,
bit 4 of the LR should be set to NOT(CONTROL.PFCA) when
an FPU is present. Current implementation is doing it for
armv8, but not for armv7. This patch makes the existing
logic applicable to both code paths.

Signed-off-by: Jean-Hugues Deschenes <jean-hugues.deschenes@ossiaco.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

diff --git a/target/arm/m_helper.c b/target/arm/m_helper.c
index 4a48b792520353556e53e3858740ceb05b0411ca..76de317e6af7c265266647f41d6bd967a27ff505 100644 (file)
--- a/target/arm/m_helper.c
+++ b/target/arm/m_helper.c
@@ -2233,19 +2233,18 @@ void arm_v7m_cpu_do_interrupt(CPUState *cs)
         if (env->v7m.secure) {
             lr |= R_V7M_EXCRET_S_MASK;
         }
-        if (!(env->v7m.control[M_REG_S] & R_V7M_CONTROL_FPCA_MASK)) {
-            lr |= R_V7M_EXCRET_FTYPE_MASK;
-        }
     } else {
         lr = R_V7M_EXCRET_RES1_MASK |
             R_V7M_EXCRET_S_MASK |
             R_V7M_EXCRET_DCRS_MASK |
-            R_V7M_EXCRET_FTYPE_MASK |
             R_V7M_EXCRET_ES_MASK;
         if (env->v7m.control[M_REG_NS] & R_V7M_CONTROL_SPSEL_MASK) {
             lr |= R_V7M_EXCRET_SPSEL_MASK;
         }
     }
+    if (!(env->v7m.control[M_REG_S] & R_V7M_CONTROL_FPCA_MASK)) {
+        lr |= R_V7M_EXCRET_FTYPE_MASK;
+    }
     if (!arm_v7m_is_handler_mode(env)) {
         lr |= R_V7M_EXCRET_MODE_MASK;
     }