tcg: Introduce TYPE_CONST temporaries

These will hold a single constant for the duration of the TB.
They are hashed, so that each value has one temp across the TB.

Not used yet, this is all infrastructure.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

1 files changed, 23 insertions, 1 deletions

diff --git a/include/tcg/tcg.h b/include/tcg/tcg.h
index e7adc7e265..eeeb70ad43 100644
--- a/include/tcg/tcg.h
+++ b/include/tcg/tcg.h
@@ -492,6 +492,8 @@ typedef enum TCGTempKind {
     TEMP_GLOBAL,
     /* Temp is in a fixed register. */
     TEMP_FIXED,
+    /* Temp is a fixed constant. */
+    TEMP_CONST,
 } TCGTempKind;
 
 typedef struct TCGTemp {
@@ -665,6 +667,7 @@ struct TCGContext {
     QSIMPLEQ_HEAD(, TCGOp) plugin_ops;
 #endif
 
+    GHashTable *const_table[TCG_TYPE_COUNT];
     TCGTempSet free_temps[TCG_TYPE_COUNT * 2];
     TCGTemp temps[TCG_MAX_TEMPS]; /* globals first, temps after */
 
@@ -681,7 +684,7 @@ struct TCGContext {
 
 static inline bool temp_readonly(TCGTemp *ts)
 {
-    return ts->kind == TEMP_FIXED;
+    return ts->kind >= TEMP_FIXED;
 }
 
 extern TCGContext tcg_init_ctx;
@@ -1079,6 +1082,7 @@ TCGOp *tcg_op_insert_after(TCGContext *s, TCGOp *op, TCGOpcode opc);
 
 void tcg_optimize(TCGContext *s);
 
+/* Allocate a new temporary and initialize it with a constant. */
 TCGv_i32 tcg_const_i32(int32_t val);
 TCGv_i64 tcg_const_i64(int64_t val);
 TCGv_i32 tcg_const_local_i32(int32_t val);
@@ -1088,6 +1092,24 @@ TCGv_vec tcg_const_ones_vec(TCGType);
 TCGv_vec tcg_const_zeros_vec_matching(TCGv_vec);
 TCGv_vec tcg_const_ones_vec_matching(TCGv_vec);
 
+/*
+ * Locate or create a read-only temporary that is a constant.
+ * This kind of temporary need not and should not be freed.
+ */
+TCGTemp *tcg_constant_internal(TCGType type, int64_t val);
+
+static inline TCGv_i32 tcg_constant_i32(int32_t val)
+{
+    return temp_tcgv_i32(tcg_constant_internal(TCG_TYPE_I32, val));
+}
+
+static inline TCGv_i64 tcg_constant_i64(int64_t val)
+{
+    return temp_tcgv_i64(tcg_constant_internal(TCG_TYPE_I64, val));
+}
+
+TCGv_vec tcg_constant_vec(TCGType type, unsigned vece, int64_t val);
+
 #if UINTPTR_MAX == UINT32_MAX
 # define tcg_const_ptr(x)        ((TCGv_ptr)tcg_const_i32((intptr_t)(x)))
 # define tcg_const_local_ptr(x)  ((TCGv_ptr)tcg_const_local_i32((intptr_t)(x)))