Merge the direct structure lookup for B::IV:: and B::NV:: into 1 routine.

As for OPs and GPs, encode the type and offset in the XS alias integer.
Use different names for the type macros, to give them different constant
values, to allow the 3 accessor routines to have no gaps in the values used
for the set of types that they deal with. Otherwise, at least 1 switch
statement would compile to a jump table with "holes".

On this platform, this refactoring reduces the object code size by 4.5K.

diff --git a/ext/B/B.xs b/ext/B/B.xs
index 42bc5e5..4eedeb9 100644 (file)
--- a/ext/B/B.xs
+++ b/ext/B/B.xs
@@ -1329,16 +1329,85 @@ IV
 SvIV(sv)
        B::IV   sv
 
-IV
-SvIVX(sv)
-       B::IV   sv
+MODULE = B     PACKAGE = B::IV
 
-UV 
-SvUVX(sv) 
-       B::IV   sv
-                      
+#define sv_SVp         0x00000
+#define sv_IVp         0x10000
+#define sv_UVp         0x20000
+#define sv_STRLENp     0x30000
+#define sv_U32p                0x40000
+#define sv_U8p         0x50000
+#define sv_char_pp     0x60000
+#define sv_NVp         0x70000
 
-MODULE = B     PACKAGE = B::IV
+#define IV_ivx_ix      sv_IVp | offsetof(struct xpviv, xiv_iv)
+#define IV_uvx_ix      sv_UVp | offsetof(struct xpvuv, xuv_uv)
+#define NV_nvx_ix      sv_NVp | offsetof(struct xpvnv, xnv_u.xnv_nv)
+
+#if PERL_VERSION >= 10
+#define NV_cop_seq_range_low_ix \
+                       sv_U32p | offsetof(struct xpvnv, xnv_u.xpad_cop_seq.xlow)
+#define NV_cop_seq_range_high_ix \
+                       sv_U32p | offsetof(struct xpvnv, xnv_u.xpad_cop_seq.xhigh)
+#define NV_parent_pad_index_ix \
+                       sv_U32p | offsetof(struct xpvnv, xnv_u.xpad_cop_seq.xlow)
+#define NV_parent_fakelex_flags_ix \
+                       sv_U32p | offsetof(struct xpvnv, xnv_u.xpad_cop_seq.xhigh)
+#else
+#define NV_cop_seq_range_low_ix \
+                       sv_NVp | offsetof(struct xpvnv, xnv_nv)
+#define NV_cop_seq_range_high_ix \
+                       sv_UVp | offsetof(struct xpvnv, xuv_uv)
+#define NV_parent_pad_index_ix \
+                       sv_NVp | offsetof(struct xpvnv, xnv_nv)
+#define NV_parent_fakelex_flags_ix \
+                       sv_UVp | offsetof(struct xpvnv, xuv_uv)
+#endif
+
+# The type checking code in B has always been identical for all SV types,
+# irrespective of whether the action is actually defined on that SV.
+# We should fix this
+void
+IVX(sv)
+       B::SV           sv
+    ALIAS:
+       B::IV::IVX = IV_ivx_ix
+       B::IV::UVX = IV_uvx_ix
+       B::NV::NVX = NV_nvx_ix
+       B::NV::COP_SEQ_RANGE_LOW = NV_cop_seq_range_low_ix
+       B::NV::COP_SEQ_RANGE_HIGH = NV_cop_seq_range_high_ix
+       B::NV::PARENT_PAD_INDEX = NV_parent_pad_index_ix
+       B::NV::PARENT_FAKELEX_FLAGS = NV_parent_fakelex_flags_ix
+    PREINIT:
+       char *ptr;
+       SV *ret;
+    PPCODE:
+       ptr = (ix & 0xFFFF) + (char *)SvANY(sv);
+       switch ((U8)(ix >> 16)) {
+       case (U8)(sv_SVp >> 16):
+           ret = make_sv_object(aTHX_ NULL, *((SV **)ptr));
+           break;
+       case (U8)(sv_IVp >> 16):
+           ret = sv_2mortal(newSViv(*((IV *)ptr)));
+           break;
+       case (U8)(sv_UVp >> 16):
+           ret = sv_2mortal(newSVuv(*((UV *)ptr)));
+           break;
+       case (U8)(sv_U32p >> 16):
+           ret = sv_2mortal(newSVuv(*((U32 *)ptr)));
+           break;
+       case (U8)(sv_U8p >> 16):
+           ret = sv_2mortal(newSVuv(*((U8 *)ptr)));
+           break;
+       case (U8)(sv_char_pp >> 16):
+           ret = sv_2mortal(newSVpv(*((char **)ptr), 0));
+           break;
+       case (U8)(sv_NVp >> 16):
+           ret = sv_2mortal(newSVnv(*((NV *)ptr)));
+           break;
+       }
+       ST(0) = ret;
+       XSRETURN(1);
 
 void
 packiv(sv)
@@ -1388,26 +1457,6 @@ NV
 SvNV(sv)
        B::NV   sv
 
-NV
-SvNVX(sv)
-       B::NV   sv
-
-U32
-COP_SEQ_RANGE_LOW(sv)
-       B::NV   sv
-
-U32
-COP_SEQ_RANGE_HIGH(sv)
-       B::NV   sv
-
-U32
-PARENT_PAD_INDEX(sv)
-       B::NV   sv
-
-U32
-PARENT_FAKELEX_FLAGS(sv)
-       B::NV   sv
-
 #if PERL_VERSION < 11
 
 MODULE = B     PACKAGE = B::RV         PREFIX = Sv