diff options
Diffstat (limited to 'compiler/cmm')
| -rw-r--r-- | compiler/cmm/CmmLint.hs | 11 | ||||
| -rw-r--r-- | compiler/cmm/PprC.hs | 3 |
2 files changed, 10 insertions, 4 deletions
diff --git a/compiler/cmm/CmmLint.hs b/compiler/cmm/CmmLint.hs index 130dba05f9..d8d6c9bb46 100644 --- a/compiler/cmm/CmmLint.hs +++ b/compiler/cmm/CmmLint.hs @@ -88,7 +88,8 @@ cmmCheckMachOp op args = return (resultRepOfMachOp op) isWordOffsetReg (CmmGlobal Sp) = True -isWordOffsetReg (CmmGlobal Hp) = True +-- No warnings for unaligned arithmetic, which is used to tag dynamic constructor closures. +--isWordOffsetReg (CmmGlobal Hp) = True isWordOffsetReg _ = False isOffsetOp (MO_Add _) = True @@ -98,14 +99,18 @@ isOffsetOp _ = False -- This expression should be an address from which a word can be loaded: -- check for funny-looking sub-word offsets. cmmCheckWordAddress e@(CmmMachOp op [arg, CmmLit (CmmInt i _)]) - | isOffsetOp op && i `rem` fromIntegral wORD_SIZE /= 0 + | isOffsetOp op && notNodeReg arg && i `rem` fromIntegral wORD_SIZE /= 0 = cmmLintDubiousWordOffset e cmmCheckWordAddress e@(CmmMachOp op [CmmLit (CmmInt i _), arg]) - | isOffsetOp op && i `rem` fromIntegral wORD_SIZE /= 0 + | isOffsetOp op && notNodeReg arg && i `rem` fromIntegral wORD_SIZE /= 0 = cmmLintDubiousWordOffset e cmmCheckWordAddress _ = return () +-- No warnings for unaligned arithmetic with the node register, +-- which is used to extract fields from tagged constructor closures. +notNodeReg (CmmReg reg) | reg == nodeReg = False +notNodeReg _ = True lintCmmStmt :: CmmStmt -> CmmLint () lintCmmStmt stmt@(CmmAssign reg expr) = do diff --git a/compiler/cmm/PprC.hs b/compiler/cmm/PprC.hs index 77d337df93..6032dc255c 100644 --- a/compiler/cmm/PprC.hs +++ b/compiler/cmm/PprC.hs @@ -322,8 +322,9 @@ pprExpr e = case e of -> char '*' <> pprAsPtrReg r CmmLoad (CmmRegOff r off) rep - | isPtrReg r && rep == wordRep + | isPtrReg r && rep == wordRep && (off `rem` wORD_SIZE == 0) -- ToDo: check that the offset is a word multiple? + -- (For tagging to work, I had to avoid unaligned loads. --ARY) -> pprAsPtrReg r <> brackets (ppr (off `shiftR` wordShift)) CmmLoad expr rep -> |