Marge Bot pushed to branch master at Glasgow Haskell Compiler / GHC Commits: 0eef99b0 by Sven Tennie at 2025-04-24T07:34:36-04:00 RV64: Introduce J instruction (non-local jumps) and don't deallocate stack slots for J_TBL (#25738) J_TBL result in local jumps, there should not deallocate stack slots (see Note [extra spill slots].) J is for non-local jumps, these may need to deallocate stack slots. - - - - - 3 changed files: - compiler/GHC/CmmToAsm/RV64/CodeGen.hs - compiler/GHC/CmmToAsm/RV64/Instr.hs - compiler/GHC/CmmToAsm/RV64/Ppr.hs Changes: ===================================== compiler/GHC/CmmToAsm/RV64/CodeGen.hs ===================================== @@ -1481,7 +1481,7 @@ assignReg_FltCode = assignReg_IntCode genJump :: CmmExpr {-the branch target-} -> NatM InstrBlock genJump expr = do (target, _format, code) <- getSomeReg expr - return (code `appOL` unitOL (annExpr expr (B (TReg target)))) + return (code `appOL` unitOL (annExpr expr (J (TReg target)))) -- ----------------------------------------------------------------------------- -- Unconditional branches @@ -2226,5 +2226,6 @@ makeFarBranches {- only used when debugging -} _platform statics basic_blocks = BCOND {} -> long_bc_jump_size B (TBlock _) -> long_b_jump_size B (TReg _) -> 1 + J op -> instr_size (B op) BL _ _ -> 1 J_TBL {} -> 1 ===================================== compiler/GHC/CmmToAsm/RV64/Instr.hs ===================================== @@ -97,6 +97,7 @@ regUsageOfInstr platform instr = case instr of ORI dst src1 _ -> usage (regOp src1, regOp dst) XORI dst src1 _ -> usage (regOp src1, regOp dst) J_TBL _ _ t -> usage ([t], []) + J t -> usage (regTarget t, []) B t -> usage (regTarget t, []) BCOND _ l r t -> usage (regTarget t ++ regOp l ++ regOp r, []) BL t ps -> usage (t : ps, callerSavedRegisters) @@ -195,6 +196,7 @@ patchRegsOfInstr instr env = case instr of ORI o1 o2 o3 -> ORI (patchOp o1) (patchOp o2) (patchOp o3) XORI o1 o2 o3 -> XORI (patchOp o1) (patchOp o2) (patchOp o3) J_TBL ids mbLbl t -> J_TBL ids mbLbl (env t) + J t -> J (patchTarget t) B t -> B (patchTarget t) BL t ps -> BL (patchReg t) ps BCOND c o1 o2 t -> BCOND c (patchOp o1) (patchOp o2) (patchTarget t) @@ -235,6 +237,7 @@ isJumpishInstr :: Instr -> Bool isJumpishInstr instr = case instr of ANN _ i -> isJumpishInstr i J_TBL {} -> True + J {} -> True B {} -> True BL {} -> True BCOND {} -> True @@ -243,6 +246,7 @@ isJumpishInstr instr = case instr of canFallthroughTo :: Instr -> BlockId -> Bool canFallthroughTo insn bid = case insn of + J (TBlock target) -> bid == target B (TBlock target) -> bid == target BCOND _ _ _ (TBlock target) -> bid == target J_TBL targets _ _ -> all isTargetBid targets @@ -256,6 +260,7 @@ canFallthroughTo insn bid = jumpDestsOfInstr :: Instr -> [BlockId] jumpDestsOfInstr (ANN _ i) = jumpDestsOfInstr i jumpDestsOfInstr (J_TBL ids _mbLbl _r) = catMaybes ids +jumpDestsOfInstr (J t) = [id | TBlock id <- [t]] jumpDestsOfInstr (B t) = [id | TBlock id <- [t]] jumpDestsOfInstr (BCOND _ _ _ t) = [id | TBlock id <- [t]] jumpDestsOfInstr _ = [] @@ -269,6 +274,7 @@ patchJumpInstr instr patchF = case instr of ANN d i -> ANN d (patchJumpInstr i patchF) J_TBL ids mbLbl r -> J_TBL (map (fmap patchF) ids) mbLbl r + J (TBlock bid) -> J (TBlock (patchF bid)) B (TBlock bid) -> B (TBlock (patchF bid)) BCOND c o1 o2 (TBlock bid) -> BCOND c o1 o2 (TBlock (patchF bid)) _ -> panic $ "patchJumpInstr: " ++ instrCon instr @@ -475,7 +481,7 @@ allocMoreStack platform slots proc@(CmmProc info lbl live (ListGraph code)) = do block' = foldr insert_dealloc [] insns insert_dealloc insn r = case insn of - J_TBL {} -> dealloc ++ (insn : r) + J {} -> dealloc ++ (insn : r) ANN _ e -> insert_dealloc e r _other | jumpDestsOfInstr insn /= [] -> @@ -591,6 +597,8 @@ data Instr -- -- @if(o2 cond o3) op <- 1 else op <- 0@ CSET Operand Operand Operand Cond + -- | Like B, but only used for non-local jumps. Used to distinguish genJumps from others. + | J Target | -- | A jump instruction with data for switch/jump tables J_TBL [Maybe BlockId] (Maybe CLabel) Reg | -- | Unconditional jump (no linking) @@ -663,6 +671,7 @@ instrCon i = LDRU {} -> "LDRU" CSET {} -> "CSET" J_TBL {} -> "J_TBL" + J {} -> "J" B {} -> "B" BL {} -> "BL" BCOND {} -> "BCOND" ===================================== compiler/GHC/CmmToAsm/RV64/Ppr.hs ===================================== @@ -543,6 +543,7 @@ pprInstr platform instr = case instr of | otherwise -> op3 (text "\taddi") o1 o2 (OpImm (ImmInt 0)) ORI o1 o2 o3 -> op3 (text "\tori") o1 o2 o3 XORI o1 o2 o3 -> op3 (text "\txori") o1 o2 o3 + J o1 -> pprInstr platform (B o1) J_TBL _ _ r -> pprInstr platform (B (TReg r)) B l | isLabel l -> line $ text "\tjal" <+> pprOp platform x0 <> comma <+> getLabel platform l B (TReg r) -> line $ text "\tjalr" <+> pprOp platform x0 <> comma <+> pprReg W64 r <> comma <+> text "0" View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/0eef99b07f80f81d463652d11bdc2282... -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/0eef99b07f80f81d463652d11bdc2282... 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