Merge pull request #2285 from WalterBright/jmptab-for-linux

add switch jump tables for Win64, Linux, FreeBSD and OSX
dlang · Jul 3, 2013 · ded8858 · ded8858
2 parents 64e05bb + 5609df9
commit ded8858
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Showing 6 changed files with 250 additions and 30 deletions.
diff --git a/src/backend/backconfig.c b/src/backend/backconfig.c
@@ -72,6 +72,7 @@ void out_config_init(
         // Not sure we really need these two lines, try removing them later
         config.flags |= CFGnoebp;
         config.flags |= CFGalwaysframe;
+        config.flags |= CFGromable; // put switch tables in code segment
     }
     else
     {   config.exe = EX_NT;
@@ -88,7 +89,11 @@ void out_config_init(
         config.fpxmmregs = TRUE;
     }
     else
+    {
         config.exe = EX_LINUX;
+        if (!exe)
+            config.flags |= CFGromable; // put switch tables in code segment
+    }
     config.flags |= CFGnoebp;
     config.flags |= CFGalwaysframe;
     if (!exe)
@@ -106,14 +111,19 @@ void out_config_init(
     config.flags |= CFGalwaysframe;
     if (!exe)
         config.flags3 |= CFG3pic;
+    config.flags |= CFGromable; // put switch tables in code segment
 #endif
 #if TARGET_FREEBSD
     if (model == 64)
     {   config.exe = EX_FREEBSD64;
         config.fpxmmregs = TRUE;
     }
     else
+    {
         config.exe = EX_FREEBSD;
+        if (!exe)
+            config.flags |= CFGromable; // put switch tables in code segment
+    }
     config.flags |= CFGnoebp;
     config.flags |= CFGalwaysframe;
     if (!exe)
@@ -125,7 +135,11 @@ void out_config_init(
         config.fpxmmregs = TRUE;
     }
     else
+    {
         config.exe = EX_OPENBSD;
+        if (!exe)
+            config.flags |= CFGromable; // put switch tables in code segment
+    }
     config.flags |= CFGnoebp;
     config.flags |= CFGalwaysframe;
     if (!exe)
@@ -137,7 +151,11 @@ void out_config_init(
         config.fpxmmregs = TRUE;
     }
     else
+    {
         config.exe = EX_SOLARIS;
+        if (!exe)
+            config.flags |= CFGromable; // put switch tables in code segment
+    }
     config.flags |= CFGnoebp;
     config.flags |= CFGalwaysframe;
     if (!exe)

diff --git a/src/backend/cc.h b/src/backend/cc.h
@@ -541,15 +541,19 @@ typedef struct block
         // CODGEN
         struct
         {
-            targ_size_t Btablesize;     // BCswitch, BCjmptab
-            targ_size_t Btableoffset;   // BCswitch, BCjmptab
+            // For BCswitch, BCjmptab
+            targ_size_t Btablesize;     // size of generated table
+            targ_size_t Btableoffset;   // offset to start of table
+            targ_size_t Btablebase;     // offset to instruction pointer base
+
             targ_size_t Boffset;        // code offset of start of this block
             targ_size_t Bsize;          // code size of this block
             con_t       Bregcon;        // register state at block exit
             targ_size_t Btryoff;        // BCtry: offset of try block data
 
             #define Btablesize          _BLU._UD.Btablesize
             #define Btableoffset        _BLU._UD.Btableoffset
+            #define Btablebase          _BLU._UD.Btablebase
             #define Boffset             _BLU._UD.Boffset
             #define Bsize               _BLU._UD.Bsize
 //          #define Bcode               _BLU._UD.Bcode

diff --git a/src/backend/cgcod.c b/src/backend/cgcod.c
@@ -404,7 +404,9 @@ void codgen()
         for (block* b = startblock; b; b = b->Bnext)
         {
             if (b->BC == BCjmptab || b->BC == BCswitch)
-            {   b->Btableoffset = swoffset;     /* offset of sw tab */
+            {
+                swoffset = align(0,swoffset);
+                b->Btableoffset = swoffset;     /* offset of sw tab */
                 swoffset += b->Btablesize;
             }
             jmpaddr(b->Bcode);          /* assign jump addresses        */