From 397cabaae035102afb547155757fd506620b2bb2 Mon Sep 17 00:00:00 2001
From: Richard Henderson <richard.henderson@linaro.org>
Date: Sun, 1 Oct 2023 07:53:03 -0700
Subject: [PATCH] tcg: Introduce tcg_use_softmmu
MIME-Version: 1.0
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Begin disconnecting CONFIG_SOFTMMU from !CONFIG_USER_ONLY.
Introduce a variable which can be set at startup to select
one method or another for user-only.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 include/tcg/tcg.h |  8 ++++++--
 tcg/tcg-op-ldst.c | 14 +++++++-------
 tcg/tcg.c         |  9 ++++++---
 3 files changed, 19 insertions(+), 12 deletions(-)

diff --git a/include/tcg/tcg.h b/include/tcg/tcg.h
index 680ff00722..a9282cdcc6 100644
--- a/include/tcg/tcg.h
+++ b/include/tcg/tcg.h
@@ -488,11 +488,9 @@ struct TCGContext {
     int nb_ops;
     TCGType addr_type;            /* TCG_TYPE_I32 or TCG_TYPE_I64 */
 
-#ifdef CONFIG_SOFTMMU
     int page_mask;
     uint8_t page_bits;
     uint8_t tlb_dyn_max_bits;
-#endif
     uint8_t insn_start_words;
     TCGBar guest_mo;
 
@@ -573,6 +571,12 @@ static inline bool temp_readonly(TCGTemp *ts)
     return ts->kind >= TEMP_FIXED;
 }
 
+#ifdef CONFIG_USER_ONLY
+extern bool tcg_use_softmmu;
+#else
+#define tcg_use_softmmu  true
+#endif
+
 extern __thread TCGContext *tcg_ctx;
 extern const void *tcg_code_gen_epilogue;
 extern uintptr_t tcg_splitwx_diff;
diff --git a/tcg/tcg-op-ldst.c b/tcg/tcg-op-ldst.c
index df4f22c427..2b96687699 100644
--- a/tcg/tcg-op-ldst.c
+++ b/tcg/tcg-op-ldst.c
@@ -34,13 +34,13 @@
 
 static void check_max_alignment(unsigned a_bits)
 {
-#if defined(CONFIG_SOFTMMU)
     /*
      * The requested alignment cannot overlap the TLB flags.
      * FIXME: Must keep the count up-to-date with "exec/cpu-all.h".
      */
-    tcg_debug_assert(a_bits + 5 <= tcg_ctx->page_bits);
-#endif
+    if (tcg_use_softmmu) {
+        tcg_debug_assert(a_bits + 5 <= tcg_ctx->page_bits);
+    }
 }
 
 static MemOp tcg_canonicalize_memop(MemOp op, bool is64, bool st)
@@ -411,10 +411,11 @@ void tcg_gen_qemu_st_i64_chk(TCGv_i64 val, TCGTemp *addr, TCGArg idx,
  */
 static bool use_two_i64_for_i128(MemOp mop)
 {
-#ifdef CONFIG_SOFTMMU
     /* Two softmmu tlb lookups is larger than one function call. */
-    return false;
-#else
+    if (tcg_use_softmmu) {
+        return false;
+    }
+
     /*
      * For user-only, two 64-bit operations may well be smaller than a call.
      * Determine if that would be legal for the requested atomicity.
@@ -432,7 +433,6 @@ static bool use_two_i64_for_i128(MemOp mop)
     default:
         g_assert_not_reached();
     }
-#endif
 }
 
 static void canonicalize_memop_i128_as_i64(MemOp ret[2], MemOp orig)
diff --git a/tcg/tcg.c b/tcg/tcg.c
index 637b9e6870..d3a4a17ef2 100644
--- a/tcg/tcg.c
+++ b/tcg/tcg.c
@@ -226,6 +226,10 @@ static TCGAtomAlign atom_and_align_for_opc(TCGContext *s, MemOp opc,
                                            MemOp host_atom, bool allow_two_ops)
     __attribute__((unused));
 
+#ifdef CONFIG_USER_ONLY
+bool tcg_use_softmmu;
+#endif
+
 TCGContext tcg_init_ctx;
 __thread TCGContext *tcg_ctx;
 
@@ -404,13 +408,12 @@ static uintptr_t G_GNUC_UNUSED get_jmp_target_addr(TCGContext *s, int which)
     return (uintptr_t)tcg_splitwx_to_rx(&s->gen_tb->jmp_target_addr[which]);
 }
 
-#if defined(CONFIG_SOFTMMU) && !defined(CONFIG_TCG_INTERPRETER)
-static int tlb_mask_table_ofs(TCGContext *s, int which)
+static int __attribute__((unused))
+tlb_mask_table_ofs(TCGContext *s, int which)
 {
     return (offsetof(CPUNegativeOffsetState, tlb.f[which]) -
             sizeof(CPUNegativeOffsetState));
 }
-#endif
 
 /* Signal overflow, starting over with fewer guest insns. */
 static G_NORETURN
-- 
2.30.2