SPARC NCG: Keep track of destinations when doing a tabled jump

diff --git a/compiler/nativeGen/MachCodeGen.hs b/compiler/nativeGen/MachCodeGen.hs
index da2b0ea..cac9f17 100644 (file)
--- a/compiler/nativeGen/MachCodeGen.hs
+++ b/compiler/nativeGen/MachCodeGen.hs
@@ -4309,8 +4309,8 @@ genSwitch expr ids
                        , SLL   e_reg (RIImm $ ImmInt 2) offset_reg
 
                        -- load and jump to the destination
-                       , LD    II32 (AddrRegReg base_reg offset_reg) dst
-                       , JMP   (AddrRegImm dst (ImmInt 0)) 
+                       , LD      II32 (AddrRegReg base_reg offset_reg) dst
+                       , JMP_TBL (AddrRegImm dst (ImmInt 0)) [i | Just i <- ids]
                        , NOP ]
 
 #else

diff --git a/compiler/nativeGen/MachInstrs.hs b/compiler/nativeGen/MachInstrs.hs
index e16dbf3..529da0d 100644 (file)
--- a/compiler/nativeGen/MachInstrs.hs
+++ b/compiler/nativeGen/MachInstrs.hs
@@ -609,6 +609,13 @@ is_G_instr instr
              | BF            Cond Bool BlockId -- cond, annul?, target
 
              | JMP           AddrMode     -- target
+
+             -- With a tabled jump we know all the possible destinations. Tabled
+             -- jump includes its list of destinations so we can work out what regs
+             -- are live across the jump.
+             -- 
+             | JMP_TBL       AddrMode [BlockId]
+
              | CALL          (Either Imm Reg) Int Bool -- target, args, terminal
 
 riZero :: RI -> Bool

diff --git a/compiler/nativeGen/PprMach.hs b/compiler/nativeGen/PprMach.hs
index 8fc9e3d..9e85198 100644 (file)
--- a/compiler/nativeGen/PprMach.hs
+++ b/compiler/nativeGen/PprMach.hs
@@ -2110,6 +2110,7 @@ pprInstr (BF cond b (BlockId id))
     ]
 
 pprInstr (JMP addr) = (<>) (ptext (sLit "\tjmp\t")) (pprAddr addr)
+pprInstr (JMP_TBL op ids)  = pprInstr (JMP op)
 
 pprInstr (CALL (Left imm) n _)
   = hcat [ ptext (sLit "\tcall\t"), pprImm imm, comma, int n ]

diff --git a/compiler/nativeGen/RegAllocInfo.hs b/compiler/nativeGen/RegAllocInfo.hs
index deb5f34..bab6c2f 100644 (file)
--- a/compiler/nativeGen/RegAllocInfo.hs
+++ b/compiler/nativeGen/RegAllocInfo.hs
@@ -320,8 +320,8 @@ regUsage instr = case instr of
     FSUB  s r1 r2 r3   -> usage ([r1, r2], [r3])
     FxTOy s1 s2 r1 r2  -> usage ([r1], [r2])
 
-    -- We assume that all local jumps will be BI/BF.  JMP must be out-of-line.
-    JMP   addr                 -> usage (regAddr addr, [])
+    JMP     addr       -> usage (regAddr addr, [])
+    JMP_TBL addr ids    -> usage (regAddr addr, [])
 
     CALL  (Left imm)  n True  -> noUsage
     CALL  (Left imm)  n False -> usage (argRegs n, callClobberedRegs)
@@ -427,6 +427,7 @@ jumpDests insn acc
 #elif sparc_TARGET_ARCH
        BI   _ _ id     -> id : acc
        BF   _ _ id     -> id : acc
+       JMP_TBL _ ids   -> ids ++ acc
 #else
 #error "RegAllocInfo.jumpDests not finished"
 #endif
@@ -696,7 +697,10 @@ patchRegs instr env = case instr of
     FSQRT s r1 r2       -> FSQRT s (env r1) (env r2)
     FSUB  s r1 r2 r3    -> FSUB s (env r1) (env r2) (env r3)
     FxTOy s1 s2 r1 r2   -> FxTOy s1 s2 (env r1) (env r2)
-    JMP   addr          -> JMP (fixAddr addr)
+
+    JMP     addr        -> JMP     (fixAddr addr)
+    JMP_TBL addr ids    -> JMP_TBL (fixAddr addr) ids
+
     CALL  (Left i) n t  -> CALL (Left i) n t
     CALL  (Right r) n t -> CALL (Right (env r)) n t
     _ -> instr