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+alignment may overlap the TLB flags
+
+Hi,
+In QEMU-4.2.0, or git-9b26a610936deaf436af9b7e39e4b7f0a35e4409, alignment may overlap the TLB flags. 
+For example, the alignment: MO_ALIGN_32,
+    MO_ALIGN_32 = 5 << MO_ASHIFT,
+and the TLB flag: TLB_DISCARD_WRITE
+#define TLB_DISCARD_WRITE   (1 << (TARGET_PAGE_BITS_MIN - 6))
+
+then, in the function "get_alignment_bits", the assert may fail:
+
+#if defined(CONFIG_SOFTMMU)
+    /* The requested alignment cannot overlap the TLB flags.  */
+    tcg_debug_assert((TLB_FLAGS_MASK & ((1 << a) - 1)) == 0);
+#endif
+
+However, the alignment of MO_ALIGN_32 is not used for now, so the assert cannot be triggered in current version. Anyway it seems like a potential conflict.
+
+That is of course completely dependent on the target page size.  So, yes, a target with a very small page size cannot use large alignments.  The assert makes sure.
+
+Is this comment simply by inspection, or did you have an actual bug to report?
+
+This is an inspection yet.
+For ARM SMMU simulation, TARGET_PAGE_BITS_MIN is 10. All low bits of the TLB virtual address are used up by TLB flags and alignment flags. It's a little crowded.
+/*
+ * ARMv7 and later CPUs have 4K pages minimum, but ARMv5 and v6
+ * have to support 1K tiny pages.
+ */
+# define TARGET_PAGE_BITS_VARY
+# define TARGET_PAGE_BITS_MIN  10
+