24a083f · Idris-dev · git.iko.soy

git.iko.soy/Idris-dev

Small runtime performance tweak

Avoiding needless setting values when we're going to write there anyway.

commit24a083f3ae5a28427959a453a9671f98de065325 authorEdwin Brady <ecb10@st-andrews.ac.uk> dateSat 28 Sep 2019, 20:31 (7 years ago) parentac930f3

3 files changed+8−2

compare with master

unifiedsplit

rts/idris_rts.h+3 src/IRTS/Bytecode.hs+3−2 src/IRTS/CodegenC.hs+2

rts/idris_rts.h+3

@@ -291,6 +291,9 @@ typedef intptr_t i_int;

291291 if (vm->valstack_top+(x) > vm->stack_max) { stackOverflow(); } \

292292 else { memset(vm->valstack_top, 0, (x)*sizeof(VAL)); } \

293293 } while(0)

294+#define RESERVENOALLOC(x) do { \

295+ if (vm->valstack_top+(x) > vm->stack_max) { stackOverflow(); } \

296+ } while(0)

294297#define ADDTOP(x) vm->valstack_top += (x)

295298#define TOPBASE(x) vm->valstack_top = vm->valstack_base + (x)

296299#define BASETOP(x) vm->valstack_base = vm->valstack_top + (x)

src/IRTS/Bytecode.hs+3−2

@@ -86,6 +86,7 @@ data BC =

8686 -- | reserve n more stack items (i.e. check there's space, grow if

8787 -- necessary)

8888 | RESERVE Int

89+ | RESERVENOALLOC Int

8990

9091 -- | move the top of stack up

9192 | ADDTOP Int

@@ -127,13 +128,13 @@ bc reg (SV (Loc i)) r = assign reg (L i) ++ clean r

127128bc reg (SApp False f vs) r =

128129 if argCount == 0

129130 then moveReg 0 vs ++ [STOREOLD, BASETOP 0, CALL f] ++ ret

130− else RESERVE argCount : moveReg 0 vs ++

131+ else RESERVENOALLOC argCount : moveReg 0 vs ++

131132 [STOREOLD, BASETOP 0, ADDTOP argCount, CALL f] ++ ret

132133 where

133134 ret = assign reg RVal ++ clean r

134135 argCount = length vs

135136bc reg (SApp True f vs) r

136− = RESERVE (length vs) : moveReg 0 vs

137+ = RESERVENOALLOC (length vs) : moveReg 0 vs

137138 ++ [SLIDE (length vs), TOPBASE (length vs), TAILCALL f]

138139bc reg (SForeign t fname args) r

139140 = FOREIGNCALL reg t fname (map farg args) : clean r

src/IRTS/CodegenC.hs+2

@@ -321,6 +321,8 @@ bcc f i (SLIDE n) = indent i ++ "SLIDE(vm, " ++ show n ++ ");\n"

321321bcc f i REBASE = indent i ++ "REBASE;\n"

322322bcc f i (RESERVE 0) = ""

323323bcc f i (RESERVE n) = indent i ++ "RESERVE(" ++ show n ++ ");\n"

324+bcc f i (RESERVENOALLOC 0) = ""

325+bcc f i (RESERVENOALLOC n) = indent i ++ "RESERVENOALLOC(" ++ show n ++ ");\n"

324326bcc f i (ADDTOP 0) = ""

325327bcc f i (ADDTOP n) = indent i ++ "ADDTOP(" ++ show n ++ ");\n"

326328bcc f i (TOPBASE n) = indent i ++ "TOPBASE(" ++ show n ++ ");\n"