diff options
Diffstat (limited to 'src/cmd/8g/ggen.c')
| -rw-r--r-- | src/cmd/8g/ggen.c | 49 |
1 files changed, 28 insertions, 21 deletions
diff --git a/src/cmd/8g/ggen.c b/src/cmd/8g/ggen.c index 5e3140480..6333a60bb 100644 --- a/src/cmd/8g/ggen.c +++ b/src/cmd/8g/ggen.c @@ -157,7 +157,7 @@ void clearfat(Node *nl) { uint32 w, c, q; - Node n1; + Node n1, z; Prog *p; /* clear a fat object */ @@ -172,6 +172,32 @@ clearfat(Node *nl) c = w % 4; // bytes q = w / 4; // quads + if(q < 4) { + // Write sequence of MOV 0, off(base) instead of using STOSL. + // The hope is that although the code will be slightly longer, + // the MOVs will have no dependencies and pipeline better + // than the unrolled STOSL loop. + // NOTE: Must use agen, not igen, so that optimizer sees address + // being taken. We are not writing on field boundaries. + regalloc(&n1, types[tptr], N); + agen(nl, &n1); + n1.op = OINDREG; + nodconst(&z, types[TUINT64], 0); + while(q-- > 0) { + n1.type = z.type; + gins(AMOVL, &z, &n1); + n1.xoffset += 4; + } + nodconst(&z, types[TUINT8], 0); + while(c-- > 0) { + n1.type = z.type; + gins(AMOVB, &z, &n1); + n1.xoffset++; + } + regfree(&n1); + return; + } + nodreg(&n1, types[tptr], D_DI); agen(nl, &n1); gconreg(AMOVL, 0, D_AX); @@ -184,7 +210,7 @@ clearfat(Node *nl) p = gins(ADUFFZERO, N, N); p->to.type = D_ADDR; p->to.sym = linksym(pkglookup("duffzero", runtimepkg)); - // 1 and 128 = magic constants: see ../../pkg/runtime/asm_386.s + // 1 and 128 = magic constants: see ../../runtime/asm_386.s p->to.offset = 1*(128-q); } else while(q > 0) { @@ -210,28 +236,12 @@ clearfat(Node *nl) void ginscall(Node *f, int proc) { - int32 arg; Prog *p; Node reg, r1, con; if(f->type != T) setmaxarg(f->type); - arg = -1; - // Most functions have a fixed-size argument block, so traceback uses that during unwind. - // Not all, though: there are some variadic functions in package runtime, - // and for those we emit call-specific metadata recorded by caller. - // Reflect generates functions with variable argsize (see reflect.methodValueCall/makeFuncStub), - // so we do this for all indirect calls as well. - if(f->type != T && (f->sym == S || (f->sym != S && f->sym->pkg == runtimepkg) || proc == 1 || proc == 2)) { - arg = f->type->argwid; - if(proc == 1 || proc == 2) - arg += 2*widthptr; - } - - if(arg != -1) - gargsize(arg); - switch(proc) { default: fatal("ginscall: bad proc %d", proc); @@ -293,9 +303,6 @@ ginscall(Node *f, int proc) } break; } - - if(arg != -1) - gargsize(-1); } /* |