[Guile-commits] 356/437: ARM: Do not limit to 24 bit displacement jump to unknown address

[Andy Wingo]

wingo pushed a commit to branch lightning
in repository guile.

commit 6db38b75e92b6d32559551a33dff19d15ced21a5
Author: Paulo Andrade <address@hidden>
Date:   Sat Jan 31 15:59:25 2015 -0200

    ARM: Do not limit to 24 bit displacement jump to unknown address
    
        * lib/jit_arm-cpu.c, lib/jit_arm.c: Only limit to 24 bit
        displacement non conditional jump in the same jit_state_t.
---
 ChangeLog         |  5 +++++
 lib/jit_arm-cpu.c | 63 ++++++++++++++++++++++++++++++++-----------------------
 lib/jit_arm.c     |  6 ++++--
 3 files changed, 46 insertions(+), 28 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 22b52dd..29f7dac 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2015-01-31 Paulo Andrade <address@hidden>
+
+       * lib/jit_arm-cpu.c, lib/jit_arm.c: Only limit to 24 bit
+       displacement non conditional jump in the same jit_state_t.
+
 2015-01-19 Paulo Andrade <address@hidden>
 
        * doc/body.texi: Reorder documentation, making jit_frame
diff --git a/lib/jit_arm-cpu.c b/lib/jit_arm-cpu.c
index 6f4ae6f..a54b4ef 100644
--- a/lib/jit_arm-cpu.c
+++ b/lib/jit_arm-cpu.c
@@ -966,8 +966,8 @@ static void 
_nei(jit_state_t*,jit_int32_t,jit_int32_t,jit_word_t);
 static void _jmpr(jit_state_t*,jit_int32_t);
 #  define jmpi(i0)                     _jmpi(_jit,i0)
 static void _jmpi(jit_state_t*,jit_word_t);
-#  define jmpi_p(i0)                   _jmpi_p(_jit,i0)
-static jit_word_t _jmpi_p(jit_state_t*,jit_word_t);
+#  define jmpi_p(i0, i1)               _jmpi_p(_jit,i0, i1)
+static jit_word_t _jmpi_p(jit_state_t*,jit_word_t,jit_bool_t);
 #  define bccr(cc,i0,r0,r1)            _bccr(_jit,cc,i0,r0,r1)
 static jit_word_t _bccr(jit_state_t*,int,jit_word_t,jit_int32_t,jit_int32_t);
 #  define bcci(cc,i0,r0,i1)            _bcci(_jit,cc,i0,r0,i1)
@@ -2570,52 +2570,63 @@ _jmpi(jit_state_t *_jit, jit_word_t i0)
 {
     jit_word_t         w;
     jit_word_t         d;
+    jit_int32_t                reg;
     w = _jit->pc.w;
     /* if thumb and in thumb mode */
     if (jit_thumb_p() && _jitc->thumb) {
        d = ((i0 - w) >> 1) - 2;
        if (d >= -1024 && d <= 1023)
            T1_B(d & 0x7ff);
-       else {
-           assert(_s24P(d));
+       else if (_s24P(d))
            T2_B(encode_thumb_jump(d));
+       else {
+           reg = jit_get_reg(jit_class_gpr|jit_class_nospill);
+           movi(rn(reg), i0);
+           jmpr(rn(reg));
+           jit_unget_reg(reg);
        }
     }
     else {
        d = ((i0 - w) >> 2) - 2;
-       assert(_s24P(d));
-       B(d & 0x00ffffff);
+       if (_s24P(d))
+           B(d & 0x00ffffff);
+       else {
+           reg = jit_get_reg(jit_class_gpr|jit_class_nospill);
+           movi(rn(reg), i0);
+           jmpr(rn(reg));
+           jit_unget_reg(reg);
+       }
     }
 }
 
 static jit_word_t
-_jmpi_p(jit_state_t *_jit, jit_word_t i0)
+_jmpi_p(jit_state_t *_jit, jit_word_t i0, jit_bool_t i1)
 {
-#if 0
-    jit_word_t         w;
-    jit_int32_t                reg;
-    reg = jit_get_reg(jit_class_gpr|jit_class_nospill);
-    w = movi_p(rn(reg), i0);
-    jmpr(rn(reg));
-    jit_unget_reg(reg);
-    return (w);
-#else
     jit_word_t         w;
     jit_word_t         d;
-    w = _jit->pc.w;
-    /* if thumb and in thumb mode */
-    if (jit_thumb_p() && _jitc->thumb) {
-       d = ((i0 - w) >> 1) - 2;
-       assert(_s24P(d));
-       T2_B(encode_thumb_jump(d));
+    jit_int32_t                reg;
+    if (i1) {
+       /* Assume jump is not longer than 23 bits if inside jit */
+       w = _jit->pc.w;
+       /* if thumb and in thumb mode */
+       if (jit_thumb_p() && _jitc->thumb) {
+           d = ((i0 - w) >> 1) - 2;
+           assert(_s24P(d));
+           T2_B(encode_thumb_jump(d));
+       }
+       else {
+           d = ((i0 - w) >> 2) - 2;
+           assert(_s24P(d));
+           B(d & 0x00ffffff);
+       }
     }
     else {
-       d = ((i0 - w) >> 2) - 2;
-       assert(_s24P(d));
-       B(d & 0x00ffffff);
+       reg = jit_get_reg(jit_class_gpr|jit_class_nospill);
+       w = movi_p(rn(reg), i0);
+       jmpr(rn(reg));
+       jit_unget_reg(reg);
     }
     return (w);
-#endif
 }
 
 static jit_word_t
diff --git a/lib/jit_arm.c b/lib/jit_arm.c
index e0e680f..6edac94 100644
--- a/lib/jit_arm.c
+++ b/lib/jit_arm.c
@@ -1555,7 +1555,8 @@ _emit_code(jit_state_t *_jit)
                    if (temp->flag & jit_flag_patch)
                        jmpi(temp->u.w);
                    else {
-                       word = jmpi_p(_jit->pc.w);
+                       word = jmpi_p(_jit->pc.w,
+                                     !!(node->flag & jit_flag_node));
                        patch(word, node);
                    }
                }
@@ -2002,7 +2003,8 @@ _patch(jit_state_t *_jit, jit_word_t instr, jit_node_t 
*node)
     }
     else {
        flag = node->u.n->flag;
-       if (node->code == jit_code_calli)
+       if (node->code == jit_code_calli ||
+           (node->code == jit_code_jmpi && !(node->flag & jit_flag_node)))
            kind = arm_patch_word;
        else
            kind = arm_patch_jump;