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| author | John Ericson <John.Ericson@Obsidian.Systems> | 2021-03-14 03:31:21 +0000 |
|---|---|---|
| committer | John Ericson <John.Ericson@Obsidian.Systems> | 2021-03-17 22:37:11 +0000 |
| commit | 9b91e63a67750e99f6915c65f428b7a613cc0005 (patch) | |
| tree | fdec9a5a75aa3218fad6de984b2fb603d455a103 | |
| parent | 43a64744458dcec82102d6daf488c33b99f24745 (diff) | |
| download | haskell-9b91e63a67750e99f6915c65f428b7a613cc0005.tar.gz | |
Fix literals for unregisterized backend of small typeswip/print-c-cast-not-suffix
All credit to @hsyl20, who in
https://gitlab.haskell.org/ghc/ghc/-/merge_requests/4717#note_338560
figured out this was a problem.
To fix this, we use casts in addition to the shrinking and suffixing
that is already done. It might make for more verbose code, I don't think
that matters too much.
In the future, perhaps some of the shrinking and suffixing can be
removed for being redundant. That proved less trivial than it sounds, so
this wasn't done at this time.
Progress towards #19026
Metric Increase:
T12707
T13379
Co-authored-by: Sylvain Henry <hsyl20@gmail.com>
| -rw-r--r-- | compiler/GHC/CmmToC.hs | 21 |
1 files changed, 16 insertions, 5 deletions
diff --git a/compiler/GHC/CmmToC.hs b/compiler/GHC/CmmToC.hs index d7596f0aac..49f0567a81 100644 --- a/compiler/GHC/CmmToC.hs +++ b/compiler/GHC/CmmToC.hs @@ -1304,13 +1304,24 @@ wordShift platform = widthInLog (wordWidth platform) commafy :: [SDoc] -> SDoc commafy xs = hsep $ punctuate comma xs --- Print in C hex format: 0x13fa +-- | Print in C hex format +-- +-- Examples: +-- +-- 5114 :: W32 ===> ((StgWord32)0x13faU) +-- (-5114) :: W32 ===> ((StgWord32)(-0x13faU)) +-- +-- We use casts to support types smaller than `unsigned int`; C literal +-- suffixes support longer but not shorter types. pprHexVal :: Platform -> Integer -> Width -> SDoc -pprHexVal platform w rep - | w < 0 = parens (char '-' <> - text "0x" <> intToDoc (-w) <> repsuffix rep) - | otherwise = text "0x" <> intToDoc w <> repsuffix rep +pprHexVal platform w rep = parens ctype <> rawlit where + rawlit + | w < 0 = parens (char '-' <> + text "0x" <> intToDoc (-w) <> repsuffix rep) + | otherwise = text "0x" <> intToDoc w <> repsuffix rep + ctype = machRep_U_CType platform rep + -- type suffix for literals: -- Integer literals are unsigned in Cmm/C. We explicitly cast to -- signed values for doing signed operations, but at all other |