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author | Ben Gamari <ben@well-typed.com> | 2022-06-23 12:41:12 -0400 |
---|---|---|
committer | Zubin Duggal <zubin.duggal@gmail.com> | 2022-07-14 14:39:37 +0530 |
commit | 85aa822901b0d1b50c95fd25261da2e4aa0e8e41 (patch) | |
tree | 47f7e7f56664eb54dc71c605af0d5dbe6a468fac | |
parent | ae114f51337c734444ddf1295f26442d9d7fcb43 (diff) | |
download | haskell-85aa822901b0d1b50c95fd25261da2e4aa0e8e41.tar.gz |
CmmToAsm/AArch64: Sign-extend narrow C arguments
The AArch64/Darwin ABI requires that function arguments narrower
than 32-bits must be sign-extended by the caller. We neglected to
do this, resulting in #20735.
Fixes #20735.
(cherry picked from commit 696d64c347364ce75e23d37884ec0bd2543b0a6a)
-rw-r--r-- | compiler/GHC/CmmToAsm/AArch64/CodeGen.hs | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/compiler/GHC/CmmToAsm/AArch64/CodeGen.hs b/compiler/GHC/CmmToAsm/AArch64/CodeGen.hs index 01881d9e8b..4f72d26959 100644 --- a/compiler/GHC/CmmToAsm/AArch64/CodeGen.hs +++ b/compiler/GHC/CmmToAsm/AArch64/CodeGen.hs @@ -1619,9 +1619,21 @@ genCCall target dest_regs arg_regs bid = do -- size we want to pack. Failure to get this right can result in pretty -- subtle bugs, e.g. #20137. - passArguments pack (gpReg:gpRegs) fpRegs ((r, format, _hint, code_r):args) stackSpace accumRegs accumCode | isIntFormat format = do + passArguments pack (gpReg:gpRegs) fpRegs ((r, format, hint, code_r):args) stackSpace accumRegs accumCode | isIntFormat format = do + platform <- getPlatform let w = formatToWidth format - mov = MOV (OpReg w gpReg) (OpReg w r) + mov + -- Specifically, Darwin/AArch64's ABI requires that the caller + -- sign-extend arguments which are smaller than 32-bits. + | w < W32 + , platformCConvNeedsExtension platform + , SignedHint <- hint + = case w of + W8 -> SXTB (OpReg W64 gpReg) (OpReg w r) + W16 -> SXTH (OpReg W64 gpReg) (OpReg w r) + _ -> panic "impossible" + | otherwise + = MOV (OpReg w gpReg) (OpReg w r) accumCode' = accumCode `appOL` code_r `snocOL` ann (text "Pass gp argument: " <> ppr r) mov |