1.0.5.27: Stepper support for MIPS.

diff --git a/NEWS b/NEWS
index cc058db..1d2fec2 100644 (file)
--- a/NEWS
+++ b/NEWS
@@ -7,6 +7,7 @@ changes in sbcl-1.0.6 relative to sbcl-1.0.5:
     (thanks to Kevin Reid)
   * enhancement: stepping is now once again supported on the SPARC.  (It is
     also now more likely to work on CheneyGC builds on the PPC.)
+  * enhancement: Stepping support on MIPS.
   * incompatible change: PURIFY no longer copies the data from the 
     dynamic space into the static and read-only spaces on platforms
     that use the generational garbage collector

diff --git a/src/compiler/mips/call.lisp b/src/compiler/mips/call.lisp
index 439541f..8ceb602 100644 (file)
--- a/src/compiler/mips/call.lisp
+++ b/src/compiler/mips/call.lisp
@@ -656,10 +656,7 @@ default-value-8
             step-instrumenting)
 
      (:ignore ,@(unless (or variable (eq return :tail)) '(arg-locs))
-              ,@(unless variable '(args))
-              ;; Step instrumentation for full calls not implemented yet.
-              ;; See the PPC backend for an example.
-              step-instrumenting)
+              ,@(unless variable '(args)))
 
      (:temporary (:sc descriptor-reg
                   :offset ocfp-offset
@@ -700,6 +697,8 @@ default-value-8
      ,@(when (eq return :fixed)
          '((:temporary (:scs (descriptor-reg) :from :eval) move-temp)))
 
+     (:temporary (:scs (descriptor-reg) :to :eval) stepping)
+
      ,@(unless (eq return :tail)
          '((:temporary (:scs (non-descriptor-reg)) temp)
            (:temporary (:sc control-stack :offset nfp-save-offset) nfp-save)))
@@ -714,6 +713,7 @@ default-value-8
        (let* ((cur-nfp (current-nfp-tn vop))
               ,@(unless (eq return :tail)
                   '((lra-label (gen-label))))
+              (step-done-label (gen-label))
               (filler
                (remove nil
                        (list :load-nargs
@@ -779,7 +779,29 @@ default-value-8
                                          (move cfp-tn csp-tn)))
                                (trace-table-entry trace-table-call-site))))
                       ((nil)
-                       (inst nop))))))
+                       (inst nop)))))
+                (insert-step-instrumenting (callable-tn)
+                  ;; Conditionally insert a conditional trap:
+                  (when step-instrumenting
+                    ;; Get the symbol-value of SB!IMPL::*STEPPING*
+                    (inst lw stepping null-tn
+                          (- (+ symbol-value-slot
+                                (truncate (static-symbol-offset 'sb!impl::*stepping*)
+                                          n-word-bytes))
+                             other-pointer-lowtag))
+                    ;; If it's not null, trap.
+                    (inst beq stepping step-done-label)
+                    (inst nop)
+                    ;; CONTEXT-PC will be pointing here when the
+                    ;; interrupt is handled, not after the BREAK.
+                    (note-this-location vop :step-before-vop)
+                    ;; Construct a trap code with the low bits from
+                    ;; SINGLE-STEP-AROUND-TRAP and the high bits from
+                    ;; the register number of CALLABLE-TN.
+                    (inst break (logior single-step-around-trap
+                                        (ash (reg-tn-encoding callable-tn)
+                                             5)))
+                    (emit-label step-done-label))))
 
            ,@(if named
                  `((sc-case name
@@ -793,6 +815,10 @@ default-value-8
                             (- (ash (tn-offset name) word-shift)
                                other-pointer-lowtag))
                       (do-next-filler)))
+                   ;; The step instrumenting must be done after
+                   ;; FUNCTION is loaded, but before ENTRY-POINT is
+                   ;; calculated.
+                   (insert-step-instrumenting name-pass)
                    (inst lw entry-point name-pass
                          (- (ash fdefn-raw-addr-slot word-shift)
                             other-pointer-lowtag))
@@ -812,6 +838,10 @@ default-value-8
                          (- (ash closure-fun-slot word-shift)
                             fun-pointer-lowtag))
                    (do-next-filler)
+                   ;; The step instrumenting must be done before
+                   ;; after FUNCTION is loaded, but before ENTRY-POINT
+                   ;; is calculated.
+                   (insert-step-instrumenting function)
                    (inst addu entry-point function
                          (- (ash simple-fun-code-offset word-shift)
                             fun-pointer-lowtag))))
@@ -1257,8 +1287,23 @@ default-value-8
 ;;; Single-stepping
 
 (define-vop (step-instrument-before-vop)
+  (:temporary (:scs (descriptor-reg)) stepping)
   (:policy :fast-safe)
   (:vop-var vop)
   (:generator 3
-    ;; Stub! See the PPC backend for an example.
-    (note-this-location vop :step-before-vop)))
+    ;; Get the symbol-value of SB!IMPL::*STEPPING*
+    (inst lw stepping null-tn
+          (- (+ symbol-value-slot
+                (truncate (static-symbol-offset 'sb!impl::*stepping*)
+                          n-word-bytes))
+             other-pointer-lowtag))
+    ;; If it's not null, trap.
+    (inst beq stepping DONE)
+    (inst nop)
+    ;; CONTEXT-PC will be pointing here when the interrupt is handled,
+    ;; not after the BREAK.
+    (note-this-location vop :step-before-vop)
+    ;; CALLEE-REGISTER-OFFSET isn't needed for before-traps, so we
+    ;; can just use a bare SINGLE-STEP-BEFORE-TRAP as the code.
+    (inst break single-step-before-trap)
+    DONE))

diff --git a/src/compiler/mips/insts.lisp b/src/compiler/mips/insts.lisp
index a6b7c72..8e21fd8 100644 (file)
--- a/src/compiler/mips/insts.lisp
+++ b/src/compiler/mips/insts.lisp
@@ -1085,7 +1085,11 @@
         (#.object-not-list-trap
          (nt "Object not list trap"))
         (#.object-not-instance-trap
-         (nt "Object not instance trap"))))))
+         (nt "Object not instance trap"))
+        (#.single-step-around-trap
+         (nt "Single step around trap"))
+        (#.single-step-before-trap
+         (nt "Single step before trap"))))))
 
 (define-instruction break (segment code &optional (subcode 0))
   (:declare (type (unsigned-byte 10) code subcode))

diff --git a/src/compiler/mips/parms.lisp b/src/compiler/mips/parms.lisp
index c133443..1932004 100644 (file)
--- a/src/compiler/mips/parms.lisp
+++ b/src/compiler/mips/parms.lisp
@@ -128,9 +128,6 @@
   pseudo-atomic
   object-not-list
   object-not-instance
-  ;; Stepper actually not implemented on Mips, but these constants
-  ;; are still needed to avoid undefined variable warnings during sbcl
-  ;; build.
   single-step-around
   single-step-before)
 

diff --git a/src/runtime/mips-arch.c b/src/runtime/mips-arch.c
index 1d6b127..6da8579 100644 (file)
--- a/src/runtime/mips-arch.c
+++ b/src/runtime/mips-arch.c
@@ -386,19 +386,30 @@ arch_handle_after_breakpoint(os_context_t *context)
     *os_context_sigmask_addr(context) = orig_sigmask;
 }
 
+void
+arch_handle_single_step_trap(os_context_t *context, int trap)
+{
+    unsigned int code = *((u32 *)(*os_context_pc_addr(context)));
+    int register_offset = code >> 11 & 0x1f;
+    handle_single_step_trap(context, trap, register_offset);
+    arch_skip_instruction(context);
+}
+
 static void
 sigtrap_handler(int signal, siginfo_t *info, void *void_context)
 {
     os_context_t *context = arch_os_get_context(&void_context);
     unsigned int code = (os_context_insn(context) >> 6) & 0xfffff;
-    /* FIXME: WTF is this magic number? Needs to become a #define
-     * and go into handle_trap. */
+    /* FIXME: This magic number is pseudo-atomic-trap from parms.lisp.
+     * Genesis should provide the proper #define, but it specialcases
+     * pseudo-atomic-trap to work around some oddity on SPARC.
+     * Eventually this should go into handle_trap. */
     if (code==0x10) {
         arch_clear_pseudo_atomic_interrupted(context);
         arch_skip_instruction(context);
         interrupt_handle_pending(context);
     } else
-        handle_trap(context,code);
+        handle_trap(context,code & 0x1f);
 }
 
 #define FIXNUM_VALUE(lispobj) (((int)lispobj) >> N_FIXNUM_TAG_BITS)

diff --git a/src/runtime/win32-os.c b/src/runtime/win32-os.c
index 394ed3e..1d9635f 100644 (file)
--- a/src/runtime/win32-os.c
+++ b/src/runtime/win32-os.c
@@ -341,7 +341,7 @@ handle_exception(EXCEPTION_RECORD *exception_record,
     }
 
     if (exception_record->ExceptionCode == EXCEPTION_BREAKPOINT) {
-       unsigned char trap;
+        unsigned char trap;
         /* This is just for info in case the monitor wants to print an
          * approximation. */
         current_control_stack_pointer =

diff --git a/tests/step.impure.lisp b/tests/step.impure.lisp
index 8842874..4ee3952 100644 (file)
--- a/tests/step.impure.lisp
+++ b/tests/step.impure.lisp
@@ -14,7 +14,7 @@
 (in-package :cl-user)
 
 ;; No stepper support on some platforms.
-#-(or x86 x86-64 ppc sparc)
+#-(or x86 x86-64 ppc sparc mips)
 (sb-ext:quit :unix-status 104)
 
 (defun fib (x)

diff --git a/version.lisp-expr b/version.lisp-expr
index 85c4185..6fb9dc7 100644 (file)
--- a/version.lisp-expr
+++ b/version.lisp-expr
@@ -17,4 +17,4 @@
 ;;; checkins which aren't released. (And occasionally for internal
 ;;; versions, especially for internal versions off the main CVS
 ;;; branch, it gets hairier, e.g. "0.pre7.14.flaky4.13".)
-"1.0.5.26"
+"1.0.5.27"