Commit 0e1ea43a9d for qemu.org

commit 0e1ea43a9dc296c3ab2eab998e3e9c6c7ca488c5
Author: Richard Henderson <richard.henderson@linaro.org>
Date:   Fri Apr 17 09:31:55 2020 -0700

    tcg: Use tcg_constant_i32 with icount expander

    We must do this before we adjust tcg_out_movi_i32, lest the
    under-the-hood poking that we do for icount be broken.

    Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
    Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

diff --git a/include/exec/gen-icount.h b/include/exec/gen-icount.h
index aa4b44354a..298e01eef4 100644
--- a/include/exec/gen-icount.h
+++ b/include/exec/gen-icount.h
@@ -34,7 +34,7 @@ static inline void gen_io_end(void)

 static inline void gen_tb_start(const TranslationBlock *tb)
 {
-    TCGv_i32 count, imm;
+    TCGv_i32 count;

     tcg_ctx->exitreq_label = gen_new_label();
     if (tb_cflags(tb) & CF_USE_ICOUNT) {
@@ -48,15 +48,13 @@ static inline void gen_tb_start(const TranslationBlock *tb)
                    offsetof(ArchCPU, env));

     if (tb_cflags(tb) & CF_USE_ICOUNT) {
-        imm = tcg_temp_new_i32();
-        /* We emit a movi with a dummy immediate argument. Keep the insn index
-         * of the movi so that we later (when we know the actual insn count)
-         * can update the immediate argument with the actual insn count.  */
-        tcg_gen_movi_i32(imm, 0xdeadbeef);
+        /*
+         * We emit a sub with a dummy immediate argument. Keep the insn index
+         * of the sub so that we later (when we know the actual insn count)
+         * can update the argument with the actual insn count.
+         */
+        tcg_gen_sub_i32(count, count, tcg_constant_i32(0));
         icount_start_insn = tcg_last_op();
-
-        tcg_gen_sub_i32(count, count, imm);
-        tcg_temp_free_i32(imm);
     }

     tcg_gen_brcondi_i32(TCG_COND_LT, count, 0, tcg_ctx->exitreq_label);
@@ -74,9 +72,12 @@ static inline void gen_tb_start(const TranslationBlock *tb)
 static inline void gen_tb_end(const TranslationBlock *tb, int num_insns)
 {
     if (tb_cflags(tb) & CF_USE_ICOUNT) {
-        /* Update the num_insn immediate parameter now that we know
-         * the actual insn count.  */
-        tcg_set_insn_param(icount_start_insn, 1, num_insns);
+        /*
+         * Update the num_insn immediate parameter now that we know
+         * the actual insn count.
+         */
+        tcg_set_insn_param(icount_start_insn, 2,
+                           tcgv_i32_arg(tcg_constant_i32(num_insns)));
     }

     gen_set_label(tcg_ctx->exitreq_label);