diff options
Diffstat (limited to 'src/cmd/8g')
-rw-r--r-- | src/cmd/8g/cgen.c | 80 |
1 files changed, 75 insertions, 5 deletions
diff --git a/src/cmd/8g/cgen.c b/src/cmd/8g/cgen.c index 5988a4328..bdf728dbb 100644 --- a/src/cmd/8g/cgen.c +++ b/src/cmd/8g/cgen.c @@ -1367,7 +1367,10 @@ int componentgen(Node *nr, Node *nl) { Node nodl, nodr; + Type *t; int freel, freer; + vlong fldcount; + vlong loffset, roffset; freel = 0; freer = 0; @@ -1377,8 +1380,33 @@ componentgen(Node *nr, Node *nl) goto no; case TARRAY: - if(!isslice(nl->type)) + t = nl->type; + + // Slices are ok. + if(isslice(t)) + break; + // Small arrays are ok. + if(t->bound > 0 && t->bound <= 3 && !isfat(t->type)) + break; + + goto no; + + case TSTRUCT: + // Small structs with non-fat types are ok. + // Zero-sized structs are treated separately elsewhere. + fldcount = 0; + for(t=nl->type->type; t; t=t->down) { + if(isfat(t->type)) + goto no; + if(t->etype != TFIELD) + fatal("componentgen: not a TFIELD: %lT", t); + fldcount++; + } + if(fldcount == 0 || fldcount > 4) goto no; + + break; + case TSTRING: case TINTER: break; @@ -1399,7 +1427,7 @@ componentgen(Node *nr, Node *nl) freer = 1; } } - + // nl and nr are 'cadable' which basically means they are names (variables) now. // If they are the same variable, don't generate any code, because the // VARDEF we generate will mark the old value as dead incorrectly. @@ -1409,8 +1437,25 @@ componentgen(Node *nr, Node *nl) switch(nl->type->etype) { case TARRAY: + // componentgen for arrays. if(nl->op == ONAME) gvardef(nl); + t = nl->type; + if(!isslice(t)) { + nodl.type = t->type; + nodr.type = nodl.type; + for(fldcount=0; fldcount < t->bound; fldcount++) { + if(nr == N) + clearslim(&nodl); + else + gmove(&nodr, &nodl); + nodl.xoffset += t->type->width; + nodr.xoffset += t->type->width; + } + goto yes; + } + + // componentgen for slices. nodl.xoffset += Array_array; nodl.type = ptrto(nl->type->type); @@ -1422,7 +1467,7 @@ componentgen(Node *nr, Node *nl) gmove(&nodr, &nodl); nodl.xoffset += Array_nel-Array_array; - nodl.type = types[TUINT32]; + nodl.type = types[simtype[TUINT]]; if(nr != N) { nodr.xoffset += Array_nel-Array_array; @@ -1432,7 +1477,7 @@ componentgen(Node *nr, Node *nl) gmove(&nodr, &nodl); nodl.xoffset += Array_cap-Array_nel; - nodl.type = types[TUINT32]; + nodl.type = types[simtype[TUINT]]; if(nr != N) { nodr.xoffset += Array_cap-Array_nel; @@ -1457,7 +1502,7 @@ componentgen(Node *nr, Node *nl) gmove(&nodr, &nodl); nodl.xoffset += Array_nel-Array_array; - nodl.type = types[TUINT32]; + nodl.type = types[simtype[TUINT]]; if(nr != N) { nodr.xoffset += Array_nel-Array_array; @@ -1492,6 +1537,31 @@ componentgen(Node *nr, Node *nl) gmove(&nodr, &nodl); goto yes; + + case TSTRUCT: + if(nl->op == ONAME) + gvardef(nl); + loffset = nodl.xoffset; + roffset = nodr.xoffset; + // funarg structs may not begin at offset zero. + if(nl->type->etype == TSTRUCT && nl->type->funarg && nl->type->type) + loffset -= nl->type->type->width; + if(nr != N && nr->type->etype == TSTRUCT && nr->type->funarg && nr->type->type) + roffset -= nr->type->type->width; + + for(t=nl->type->type; t; t=t->down) { + nodl.xoffset = loffset + t->width; + nodl.type = t->type; + + if(nr == N) + clearslim(&nodl); + else { + nodr.xoffset = roffset + t->width; + nodr.type = nodl.type; + gmove(&nodr, &nodl); + } + } + goto yes; } no: |