Merge pull request #397 from dawgfoto/master

check that block displacement fits into immediate
dlang · Sep 23, 2011 · 243fd91 · 243fd91
2 parents bcc14a3 + c5e22f5
commit 243fd91
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Showing 3 changed files with 32 additions and 4 deletions.
diff --git a/src/backend/cc.h b/src/backend/cc.h
@@ -212,7 +212,7 @@ typedef struct Srcpos
 #endif
 #if MARS
     const char *Sfilename;
-    #define srcpos_name(p)      ((p).SFname)
+    #define srcpos_name(p)      ((p)->Sfilename)
 #endif
 #if M_UNIX
     short Sfilnum;              // file number

diff --git a/src/backend/cod3.c b/src/backend/cod3.c
@@ -5419,7 +5419,6 @@ STATIC void do64bit(enum FL fl,union evc *uev,int flags)
 {   char *p;
     symbol *s;
     targ_size_t ad;
-    long tmp;
 
     assert(I64);
     switch (fl)
@@ -5505,7 +5504,6 @@ STATIC void do32bit(enum FL fl,union evc *uev,int flags, targ_size_t val)
 { char *p;
   symbol *s;
   targ_size_t ad;
-  long tmp;
 
   //printf("do32bit(flags = x%x)\n", flags);
   switch (fl)
@@ -5670,6 +5668,12 @@ STATIC void do16bit(enum FL fl,union evc *uev,int flags)
         break;
     case FLblock:                       /* displacement to another block */
         ad = uev->Vblock->Boffset - OFFSET() - 2;
+#ifdef DEBUG
+        {
+            targ_ptrdiff_t delta = uev->Vblock->Boffset - OFFSET() - 2;
+            assert((signed short)delta == delta);
+        }
+#endif
     L1:
         GENP(2,&ad);                    // displacement
         return;
@@ -5690,14 +5694,23 @@ STATIC void do16bit(enum FL fl,union evc *uev,int flags)
 
 STATIC void do8bit(enum FL fl,union evc *uev)
 { char c;
+  targ_ptrdiff_t delta;
 
   switch (fl)
   {
     case FLconst:
         c = uev->Vuns;
         break;
     case FLblock:
-        c = uev->Vblock->Boffset - OFFSET() - 1;
+        delta = uev->Vblock->Boffset - OFFSET() - 1;
+        if ((signed char)delta != delta)
+        {
+            if (uev->Vblock->Bsrcpos.Slinnum)
+                fprintf(stderr, "%s(%d): ", uev->Vblock->Bsrcpos.Sfilename, uev->Vblock->Bsrcpos.Slinnum);
+            fprintf(stderr, "block displacement of %lld exceeds the maximum offset of -128 to 127.\n", (long long)delta);
+            err_exit();
+        }
+        c = delta;
 #ifdef DEBUG
         assert(uev->Vblock->Boffset > OFFSET() || c != 0x7F);
 #endif

diff --git a/test/fail_compilation/fail353.d b/test/fail_compilation/fail353.d
@@ -0,0 +1,15 @@
+void foo()
+{
+    enum NOP = 0x9090_9090_9090_9090;
+
+    asm
+    {
+    L1:
+        dq NOP,NOP,NOP,NOP;    //  32
+        dq NOP,NOP,NOP,NOP;    //  64
+        dq NOP,NOP,NOP,NOP;    //  96
+        dq NOP,NOP,NOP,NOP;    // 128
+        // unnoticed signed underflow of rel8 with DMD2.056
+        loop L1;
+    }
+}