Hexagon (target/hexagon) TCG generation cleanup

Simplify TCG generation of hex_reg_written

Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <1617930474-31979-2-git-send-email-tsimpson@quicinc.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

target/hexagon/genptr.c

@@ -35,7 +35,6 @@ static inline TCGv gen_read_preg(TCGv pred, uint8_t num)
 
 static inline void gen_log_predicated_reg_write(int rnum, TCGv val, int slot)
 {
-    TCGv one = tcg_const_tl(1);
     TCGv zero = tcg_const_tl(0);
     TCGv slot_mask = tcg_temp_new();
 
@@ -43,12 +42,17 @@ static inline void gen_log_predicated_reg_write(int rnum, TCGv val, int slot)
     tcg_gen_movcond_tl(TCG_COND_EQ, hex_new_value[rnum], slot_mask, zero,
                            val, hex_new_value[rnum]);
 #if HEX_DEBUG
-    /* Do this so HELPER(debug_commit_end) will know */
-    tcg_gen_movcond_tl(TCG_COND_EQ, hex_reg_written[rnum], slot_mask, zero,
-                       one, hex_reg_written[rnum]);
+    /*
+     * Do this so HELPER(debug_commit_end) will know
+     *
+     * Note that slot_mask indicates the value is not written
+     * (i.e., slot was cancelled), so we create a true/false value before
+     * or'ing with hex_reg_written[rnum].
+     */
+    tcg_gen_setcond_tl(TCG_COND_EQ, slot_mask, slot_mask, zero);
+    tcg_gen_or_tl(hex_reg_written[rnum], hex_reg_written[rnum], slot_mask);
 #endif
 
-    tcg_temp_free(one);
     tcg_temp_free(zero);
     tcg_temp_free(slot_mask);
 }