target/ppc: Initialize lazy_tlb_flush correctly

ppc_tr_init_disas_context() correctly sets lazy_tlb_flush to true on
certain CPU models.  However, it leaves it uninitialized, instead of
setting it to false on all others.

It wasn't caught before now because we didn't have examples in the tests
that exercised this path.  However it can now be caught using clang's
undefined behaviour sanitizer and the sam460ex board.

Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>

diff --git a/target/ppc/translate.c b/target/ppc/translate.c
index 218665b4080b3a931dde887368fc8f9021faa680..3457d29f8e3536017c1cfc4b3ee37e193ee9f1b7 100644 (file)
--- a/target/ppc/translate.c
+++ b/target/ppc/translate.c
@@ -7237,10 +7237,9 @@ static int ppc_tr_init_disas_context(DisasContextBase *dcbase,
     ctx->sf_mode = msr_is_64bit(env, env->msr);
     ctx->has_cfar = !!(env->flags & POWERPC_FLAG_CFAR);
 #endif
-    if (env->mmu_model == POWERPC_MMU_32B ||
-        env->mmu_model == POWERPC_MMU_601 ||
-        (env->mmu_model & POWERPC_MMU_64B))
-            ctx->lazy_tlb_flush = true;
+    ctx->lazy_tlb_flush = env->mmu_model == POWERPC_MMU_32B
+        || env->mmu_model == POWERPC_MMU_601
+        || (env->mmu_model & POWERPC_MMU_64B);
 
     ctx->fpu_enabled = !!msr_fp;
     if ((env->flags & POWERPC_FLAG_SPE) && msr_spe)