UNREG: PprC: add support for of W16 literals (Ticket #15237)

Fix UNREG build failure for 32-bit targets.

This change is an equivalent of commit
0238a6c7
("UNREG: PprC: add support for of W32 literals")

The change allows combining two subwords into one word
on 32-bit targets. Tested on nios2-unknown-linux-gnu.

GHC Trac Issues: #15237

Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>

compiler/cmm/PprC.hs

@@ -546,6 +546,14 @@ pprStatics dflags (CmmStaticLit (CmmInt a W32) :
                             rest)
     else pprStatics dflags (CmmStaticLit (CmmInt ((shiftL b 32) .|. a) W64) :
                             rest)
+pprStatics dflags (CmmStaticLit (CmmInt a W16) :
+                   CmmStaticLit (CmmInt b W16) : rest)
+  | wordWidth dflags == W32
+  = if wORDS_BIGENDIAN dflags
+    then pprStatics dflags (CmmStaticLit (CmmInt ((shiftL a 16) .|. b) W32) :
+                            rest)
+    else pprStatics dflags (CmmStaticLit (CmmInt ((shiftL b 16) .|. a) W32) :
+                            rest)
 pprStatics dflags (CmmStaticLit (CmmInt _ w) : _)
   | w /= wordWidth dflags
   = pprPanic "pprStatics: cannot emit a non-word-sized static literal" (ppr w)