ref: 8188b4f4f0e07b6669e6ae3c6c1099af917eaab4
dir: /sys/src/cmd/8c/machcap.c/
#include "gc.h" int machcap(Node *n) { // return 0; if(n == Z) return 1; /* test */ switch(n->op) { case OMUL: case OLMUL: case OASMUL: case OASLMUL: if(typechl[n->type->etype]) return 1; if(typev[n->type->etype]) { // if(typev[n->type->etype] && n->right->op == OCONST) { // if(hi64v(n->right) == 0) return !mixedasop(n->left->type, n->right->type); } break; case OCOM: case ONEG: case OADD: case OAND: case OOR: case OSUB: case OXOR: case OASHL: case OLSHR: case OASHR: if(typechlv[n->left->type->etype]) return 1; break; case OCAST: if(typev[n->type->etype]) { if(typechlp[n->left->type->etype]) return 1; } else if(!typefd[n->type->etype]) { if(typev[n->left->type->etype]) return 1; } break; case OCOND: case OCOMMA: case OLIST: case OANDAND: case OOROR: case ONOT: case ODOT: return 1; case OASADD: case OASSUB: return !mixedasop(n->left->type, n->right->type); case OASAND: case OASOR: case OASXOR: return 1; case OASASHL: case OASASHR: case OASLSHR: return 1; case OPOSTINC: case OPOSTDEC: case OPREINC: case OPREDEC: return 1; case OEQ: case ONE: case OLE: case OGT: case OLT: case OGE: case OHI: case OHS: case OLO: case OLS: //print("%O\n", n->op); return 1; } return 0; }