diff options
Diffstat (limited to 'src/cmd/9g/ggen.c')
| -rw-r--r-- | src/cmd/9g/ggen.c | 20 |
1 files changed, 13 insertions, 7 deletions
diff --git a/src/cmd/9g/ggen.c b/src/cmd/9g/ggen.c index c41d8eb41..7d9cf5050 100644 --- a/src/cmd/9g/ggen.c +++ b/src/cmd/9g/ggen.c @@ -900,7 +900,7 @@ ret: void clearfat(Node *nl) { - uint64 w, c, q, t; + uint64 w, c, q, t, boff; Node dst, end, r0, *f; Prog *p, *pl; @@ -944,6 +944,8 @@ clearfat(Node *nl) patch(gbranch(ABNE, T, 0), pl); regfree(&end); + // The loop leaves R3 on the last zeroed dword + boff = 8; } else if(q >= 4) { p = gins(ASUB, N, &dst); p->from.type = D_CONST; @@ -953,17 +955,21 @@ clearfat(Node *nl) afunclit(&p->to, f); // 4 and 128 = magic constants: see ../../runtime/asm_power64x.s p->to.offset = 4*(128-q); - } else - for(t = 0; t < q; t++) { - p = gins(AMOVD, &r0, &dst); - p->to.type = D_OREG; - p->to.offset = 8*t; + // duffzero leaves R3 on the last zeroed dword + boff = 8; + } else { + for(t = 0; t < q; t++) { + p = gins(AMOVD, &r0, &dst); + p->to.type = D_OREG; + p->to.offset = 8*t; + } + boff = 8*q; } for(t = 0; t < c; t++) { p = gins(AMOVB, &r0, &dst); p->to.type = D_OREG; - p->to.offset = t; + p->to.offset = t+boff; } reg[REGRT1]--; } |