tcg: Rearrange ldst label tracking

Dispense with TCGBackendData, as it has never been used for more than
holding a single pointer.  Use a define in the cpu/tcg-target.h to
signal requirement for TCGLabelQemuLdst, so that we can drop the no-op
tcg-be-null.h stubs.  Rename tcg-be-ldst.h to tcg-ldst.inc.c.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>

1 files changed, 78 insertions, 0 deletions

diff --git a/tcg/tcg-ldst.inc.c b/tcg/tcg-ldst.inc.c
new file mode 100644
index 0000000000..0e14cf4357
--- /dev/null
+++ b/tcg/tcg-ldst.inc.c
@@ -0,0 +1,78 @@
+/*
+ * TCG Backend Data: load-store optimization only.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+typedef struct TCGLabelQemuLdst {
+    bool is_ld;             /* qemu_ld: true, qemu_st: false */
+    TCGMemOpIdx oi;
+    TCGType type;           /* result type of a load */
+    TCGReg addrlo_reg;      /* reg index for low word of guest virtual addr */
+    TCGReg addrhi_reg;      /* reg index for high word of guest virtual addr */
+    TCGReg datalo_reg;      /* reg index for low word to be loaded or stored */
+    TCGReg datahi_reg;      /* reg index for high word to be loaded or stored */
+    tcg_insn_unit *raddr;   /* gen code addr of the next IR of qemu_ld/st IR */
+    tcg_insn_unit *label_ptr[2]; /* label pointers to be updated */
+    struct TCGLabelQemuLdst *next;
+} TCGLabelQemuLdst;
+
+
+/*
+ * Generate TB finalization at the end of block
+ */
+
+static void tcg_out_qemu_ld_slow_path(TCGContext *s, TCGLabelQemuLdst *l);
+static void tcg_out_qemu_st_slow_path(TCGContext *s, TCGLabelQemuLdst *l);
+
+static bool tcg_out_ldst_finalize(TCGContext *s)
+{
+    TCGLabelQemuLdst *lb;
+
+    /* qemu_ld/st slow paths */
+    for (lb = s->ldst_labels; lb != NULL; lb = lb->next) {
+        if (lb->is_ld) {
+            tcg_out_qemu_ld_slow_path(s, lb);
+        } else {
+            tcg_out_qemu_st_slow_path(s, lb);
+        }
+
+        /* Test for (pending) buffer overflow.  The assumption is that any
+           one operation beginning below the high water mark cannot overrun
+           the buffer completely.  Thus we can test for overflow after
+           generating code without having to check during generation.  */
+        if (unlikely((void *)s->code_ptr > s->code_gen_highwater)) {
+            return false;
+        }
+    }
+    return true;
+}
+
+/*
+ * Allocate a new TCGLabelQemuLdst entry.
+ */
+
+static inline TCGLabelQemuLdst *new_ldst_label(TCGContext *s)
+{
+    TCGLabelQemuLdst *l = tcg_malloc(sizeof(*l));
+
+    l->next = s->ldst_labels;
+    s->ldst_labels = l;
+    return l;
+}