5cba59e9c
Denys Vlasenko
2026-01-24
Subject
awk: use more understandable form of "split-globals" trick
Binary
No binary (build failed)
Architecture & Compiler Flags
gcc -Wp,-MD,applets/.usage.d -Wall -Wstrict-prototypes -O2 -fomit-frame-pointer -Iinclude -Iinclude -o applets/usage applets/usage.c
Build Log
(log yok)
Commit Diff GitHub →
archival/gzip.c+3 -0
| @@ -2215,6 +2215,9 @@ int gzip_main(int argc UNUSED_PARAM, char **argv) | |
| }; | |
| #endif | |
| + | // TODO: use less ugly "split-globals" trick via SET_OFFSET_PTR_TO_GLOBALS(). |
| + | // The problem is, the current method strategically places G2.heap[] |
| + | // (~24 references) so that it has zero offset. |
| SET_PTR_TO_GLOBALS((char *)xzalloc(sizeof(struct globals)+sizeof(struct globals2)) | |
| + sizeof(struct globals)); | |
editors/awk.c+33 -39
| @@ -583,14 +583,10 @@ static const char vValues[] ALIGN1 = | |
| static const uint16_t PRIMES[] ALIGN2 = { 251, 1021, 4093, 16381, 65521 }; | |
| - | /* Globals. Split in two parts so that first one is addressed |
| - | * with (mostly short) negative offsets. |
| - | * NB: it's unsafe to put members of type "double" |
| - | * into globals2 (gcc may fail to align them). |
| - | */ |
| struct globals { | |
| - | double t_double; |
| chain beginseq, mainseq, endseq; | |
| + | |
| + | double t_double; |
| chain *seq; | |
| node *break_ptr, *continue_ptr; | |
| xhash *ahash; /* argument names, used only while parsing function bodies */ | |
| @@ -618,9 +614,8 @@ struct globals { | |
| smallint next_token__concat_inserted; | |
| uint32_t next_token__save_tclass; | |
| uint32_t next_token__save_info; | |
| - | }; |
| - | struct globals2 { |
| - | uint32_t t_info; /* often used */ |
| + | |
| + | uint32_t t_info; |
| uint32_t t_tclass; | |
| char *t_string; | |
| int t_lineno; | |
| @@ -654,41 +649,40 @@ struct globals2 { | |
| char g_buf[MAXVARFMT + 1]; | |
| }; | |
| - | #define G1 (ptr_to_globals[-1]) |
| - | #define G (*(struct globals2 *)ptr_to_globals) |
| + | #define G (*OFFSET_PTR_TO_GLOBALS) |
| /* For debug. nm --size-sort awk.o | grep -vi ' [tr] ' */ | |
| //char G1size[sizeof(G1)]; // 0x70 | |
| //char Gsize[sizeof(G)]; // 0x2f8 | |
| /* Trying to keep most of members accessible with short offsets: */ | |
| //char Gofs_seed[offsetof(struct globals2, evaluate__seed)]; // 0x7c | |
| - | #define t_double (G1.t_double ) |
| - | #define beginseq (G1.beginseq ) |
| - | #define mainseq (G1.mainseq ) |
| - | #define endseq (G1.endseq ) |
| - | #define seq (G1.seq ) |
| - | #define break_ptr (G1.break_ptr ) |
| - | #define continue_ptr (G1.continue_ptr) |
| - | #define ahash (G1.ahash ) |
| - | #define fnhash (G1.fnhash ) |
| - | #define vhash (G1.vhash ) |
| + | #define t_double (G.t_double ) |
| + | #define beginseq (G.beginseq ) |
| + | #define mainseq (G.mainseq ) |
| + | #define endseq (G.endseq ) |
| + | #define seq (G.seq ) |
| + | #define break_ptr (G.break_ptr ) |
| + | #define continue_ptr (G.continue_ptr) |
| + | #define ahash (G.ahash ) |
| + | #define fnhash (G.fnhash ) |
| + | #define vhash (G.vhash ) |
| #define fdhash ahash | |
| //^^^^^^^^^^^^^^^^^^ ahash is cleared after every function parsing, | |
| // and ends up empty after parsing phase. Thus, we can simply reuse it | |
| // for fdhash in execution stage. | |
| - | #define g_progname (G1.g_progname ) |
| - | #define g_lineno (G1.g_lineno ) |
| - | #define num_fields (G1.num_fields ) |
| - | #define num_alloc_fields (G1.num_alloc_fields) |
| - | #define Fields (G1.Fields ) |
| - | #define g_pos (G1.g_pos ) |
| - | #define g_saved_ch (G1.g_saved_ch ) |
| - | #define got_program (G1.got_program ) |
| - | #define icase (G1.icase ) |
| - | #define exiting (G1.exiting ) |
| - | #define nextrec (G1.nextrec ) |
| - | #define nextfile (G1.nextfile ) |
| - | #define is_f0_split (G1.is_f0_split ) |
| - | #define t_rollback (G1.t_rollback ) |
| + | #define g_progname (G.g_progname ) |
| + | #define g_lineno (G.g_lineno ) |
| + | #define num_fields (G.num_fields ) |
| + | #define num_alloc_fields (G.num_alloc_fields) |
| + | #define Fields (G.Fields ) |
| + | #define g_pos (G.g_pos ) |
| + | #define g_saved_ch (G.g_saved_ch ) |
| + | #define got_program (G.got_program ) |
| + | #define icase (G.icase ) |
| + | #define exiting (G.exiting ) |
| + | #define nextrec (G.nextrec ) |
| + | #define nextfile (G.nextfile ) |
| + | #define is_f0_split (G.is_f0_split ) |
| + | #define t_rollback (G.t_rollback ) |
| #define t_info (G.t_info ) | |
| #define t_tclass (G.t_tclass ) | |
| #define t_string (G.t_string ) | |
| @@ -699,7 +693,7 @@ struct globals2 { | |
| #define rsplitter (G.rsplitter ) | |
| #define g_buf (G.g_buf ) | |
| #define INIT_G() do { \ | |
| - | SET_PTR_TO_GLOBALS((char*)xzalloc(sizeof(G1)+sizeof(G)) + sizeof(G1)); \ |
| + | SET_OFFSET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \ |
| t_tclass = TC_NEWLINE; \ | |
| G.evaluate__seed = 1; \ | |
| } while (0) | |
| @@ -1168,9 +1162,9 @@ static int istrue(var *v) | |
| */ | |
| static uint32_t next_token(uint32_t expected) | |
| { | |
| - | #define concat_inserted (G1.next_token__concat_inserted) |
| - | #define save_tclass (G1.next_token__save_tclass) |
| - | #define save_info (G1.next_token__save_info) |
| + | #define concat_inserted (G.next_token__concat_inserted) |
| + | #define save_tclass (G.next_token__save_tclass) |
| + | #define save_info (G.next_token__save_info) |
| char *p; | |
| const char *tl; | |