target/riscv: Improve the scause logic

No functional change, just making the code easier to read.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>

diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c
index 7318da289f6e79034c9e60a99797c88a09b83646..c577a262b8b4521bca4841230dff018347abe92e 100644 (file)
--- a/target/riscv/cpu_helper.c
+++ b/target/riscv/cpu_helper.c
@@ -515,7 +515,7 @@ void riscv_cpu_do_interrupt(CPUState *cs)
         s = set_field(s, MSTATUS_SPP, env->priv);
         s = set_field(s, MSTATUS_SIE, 0);
         env->mstatus = s;
-        env->scause = cause | ~(((target_ulong)-1) >> async);
+        env->scause = cause | ((target_ulong)async << (TARGET_LONG_BITS - 1));
         env->sepc = env->pc;
         env->sbadaddr = tval;
         env->pc = (env->stvec >> 2 << 2) +