[v12,19/27] target/arm: [tcg] Port to breakpoint_check

Commit Message

Lluís Vilanova July 7, 2017, 12:58 p.m. UTC

Incrementally paves the way towards using the generic instruction translation
loop.

Signed-off-by: Lluís Vilanova <[e-mail]>
Reviewed-by: Richard Henderson <[e-mail]>
---
 target/arm/translate.c |   64 +++++++++++++++++++++++++++++++++++-------------
 1 file changed, 46 insertions(+), 18 deletions(-)

Patch

diff --git a/target/arm/translate.c b/target/arm/translate.c
index 7a1935d4d7..29428b2920 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -11916,6 +11916,32 @@  static void arm_tr_insn_start(DisasContextBase *dcbase, CPUState *cpu)
 #endif
 }
 
+static BreakpointCheckType arm_tr_breakpoint_check(
+    DisasContextBase *dcbase, CPUState *cpu, const CPUBreakpoint *bp)
+{
+    DisasContext *dc = container_of(dcbase, DisasContext, base);
+
+    if (bp->flags & BP_CPU) {
+        gen_set_condexec(dc);
+        gen_set_pc_im(dc, dc->pc);
+        gen_helper_check_breakpoints(cpu_env);
+        /* End the TB early; it's likely not going to be executed */
+        dc->base.is_jmp = DISAS_UPDATE;
+        return BC_HIT_INSN;
+    } else {
+        gen_exception_internal_insn(dc, 0, EXCP_DEBUG);
+        /* The address covered by the breakpoint must be
+           included in [tb->pc, tb->pc + tb->size) in order
+           to for it to be properly cleared -- thus we
+           increment the PC here so that the logic setting
+           tb->size below does the right thing.  */
+        /* TODO: Advance PC by correct instruction length to
+         * avoid disassembler error messages */
+        dc->pc += 2;
+        return BC_HIT_TB;
+    }
+}
+
 /* generate intermediate code for basic block 'tb'.  */
 void gen_intermediate_code(CPUState *cs, TranslationBlock *tb)
 {
@@ -11964,29 +11990,31 @@  void gen_intermediate_code(CPUState *cs, TranslationBlock *tb)
         if (unlikely(!QTAILQ_EMPTY(&cs->breakpoints))) {
             CPUBreakpoint *bp;
             QTAILQ_FOREACH(bp, &cs->breakpoints, entry) {
-                if (bp->pc == dc->pc) {
-                    if (bp->flags & BP_CPU) {
-                        gen_set_condexec(dc);
-                        gen_set_pc_im(dc, dc->pc);
-                        gen_helper_check_breakpoints(cpu_env);
-                        /* End the TB early; it's likely not going to be executed */
-                        dc->base.is_jmp = DISAS_UPDATE;
-                    } else {
-                        gen_exception_internal_insn(dc, 0, EXCP_DEBUG);
-                        /* The address covered by the breakpoint must be
-                           included in [tb->pc, tb->pc + tb->size) in order
-                           to for it to be properly cleared -- thus we
-                           increment the PC here so that the logic setting
-                           tb->size below does the right thing.  */
-                        /* TODO: Advance PC by correct instruction length to
-                         * avoid disassembler error messages */
-                        dc->pc += 2;
+                if (bp->pc == dc->base.pc_next) {
+                    BreakpointCheckType bp_check =
+                        arm_tr_breakpoint_check(&dc->base, cs, bp);
+                    switch (bp_check) {
+                    case BC_MISS:
+                        /* Target ignored this breakpoint, go to next */
+                        break;
+                    case BC_HIT_INSN:
+                        /* Hit, keep translating */
+                        /*
+                         * TODO: if we're never going to have more than one
+                         *       BP in a single address, we can simply use a
+                         *       bool here.
+                         */
+                        goto done_breakpoints;
+                    case BC_HIT_TB:
+                        /* Hit, end TB */
                         goto done_generating;
+                    default:
+                        g_assert_not_reached();
                     }
-                    break;
                 }
             }
         }
+    done_breakpoints:
 
         if (dc->base.num_insns == max_insns && (tb->cflags & CF_LAST_IO)) {
             gen_io_start();