arm bug with stack adjust

R=r
CC=golang-dev
https://golang.org/cl/3980043

diff --git a/src/cmd/5g/opt.h b/src/cmd/5g/opt.h
index a3e3abc135ac246a9d6c59e2ca7dc9955698873a..7a0070fc9dce2a44410f9e0443f73a9b91b1e608 100644 (file)
--- a/src/cmd/5g/opt.h
+++ b/src/cmd/5g/opt.h
@@ -69,7 +69,6 @@ struct        Reg
 
        uint16  loop;           // x5 for every loop
        uchar   refset;         // diagnostic generated
-       uchar   nomove;         // funny mov instruction
 
        Reg*    p1;
        Reg*    p2;

diff --git a/src/cmd/5g/reg.c b/src/cmd/5g/reg.c
index a6d35f99779cbe7c95bf456fbd5710564e4fede4..d30d03b2060b37667ef0034f44814729abdeec04 100644 (file)
--- a/src/cmd/5g/reg.c
+++ b/src/cmd/5g/reg.c
@@ -143,7 +143,7 @@ regopt(Prog *firstp)
        first++;
 
        if(debug['K']) {
-               if(first != 4)
+               if(first != 1)
                        return;
 //             debug['R'] = 2;
 //             debug['P'] = 2;
@@ -191,21 +191,6 @@ regopt(Prog *firstp)
                case ANAME:
                case ASIGNAME:
                        continue;
-
-               case AMOVW:
-                       // mark instructions that set SP
-                       if(p->to.type == D_REG) {
-                               switch(p->to.reg) {
-                               case REGSP:
-                               case REGLINK:
-                               case REGPC:
-                                       r->nomove = 1;
-                                       break;
-                               }
-                       }
-                       if(p->scond != C_SCOND_NONE)
-                               r->nomove = 1;
-                       break;
                }
                r = rega();
                nr++;
@@ -323,6 +308,7 @@ regopt(Prog *firstp)
        if(debug['R']) {
                p = firstr->prog;
                print("\n%L %D\n", p->lineno, &p->from);
+               print(" addr = %Q\n", addrs);
        }
 
        /*
@@ -386,6 +372,7 @@ loop2:
                                        r->refahead.b[z] | r->calahead.b[z] |
                                        r->refbehind.b[z] | r->calbehind.b[z] |
                                        r->use1.b[z] | r->use2.b[z];
+                               bit.b[z] &= ~addrs.b[z];
                        }
 
                        if(bany(&bit)) {
@@ -511,18 +498,61 @@ brk:
         * last pass
         * eliminate nops
         * free aux structures
+        * adjust the stack pointer
+        *      MOVW.W  R1,-12(R13)                     <<- start
+        *      MOVW    R0,R1
+        *      MOVW    R1,8(R13)
+        *      MOVW    $0,R1
+        *      MOVW    R1,4(R13)
+        *      BL      ,runtime.newproc+0(SB)
+        *      MOVW    &ft+-32(SP),R7                  <<- adjust
+        *      MOVW    &j+-40(SP),R6                   <<- adjust
+        *      MOVW    autotmp_0003+-24(SP),R5         <<- adjust
+        *      MOVW    $12(R13),R13                    <<- finish
         */
+       vreg = 0;
        for(p = firstp; p != P; p = p->link) {
                while(p->link != P && p->link->as == ANOP)
                        p->link = p->link->link;
                if(p->to.type == D_BRANCH)
                        while(p->to.branch != P && p->to.branch->as == ANOP)
                                p->to.branch = p->to.branch->link;
+               if(p->as == AMOVW && p->to.reg == 13) {
+                       if(p->scond & C_WBIT) {
+                               vreg = -p->to.offset;           // in adjust region
+//                             print("%P adjusting %d\n", p, vreg);
+                               continue;
+                       }
+                       if(p->from.type == D_CONST && p->to.type == D_REG) {
+                               if(p->from.offset != vreg)
+                                       print("in and out different\n");
+//                             print("%P finish %d\n", p, vreg);
+                               vreg = 0;       // done adjust region
+                               continue;
+                       }
+
+//                     print("%P %d %d from type\n", p, p->from.type, D_CONST);
+//                     print("%P %d %d to type\n\n", p, p->to.type, D_REG);
+               }
+
+               if(p->as == AMOVW && vreg != 0) {
+                       if(p->from.sym != S)
+                       if(p->from.name == D_AUTO || p->from.name == D_PARAM) {
+                               p->from.offset += vreg;
+//                             print("%P adjusting from %d %d\n", p, vreg, p->from.type);
+                       }
+                       if(p->to.sym != S)
+                       if(p->to.name == D_AUTO || p->to.name == D_PARAM) {
+                               p->to.offset += vreg;
+//                             print("%P adjusting to %d %d\n", p, vreg, p->from.type);
+                       }
+               }
        }
        if(r1 != R) {
                r1->link = freer;
                freer = firstr;
        }
+
 }
 
 void
@@ -1208,12 +1238,6 @@ paint3(Reg *r, int bn, int32 rb, int rn)
                r = r1;
        }
 
-       // horrible hack to prevent loading a
-       // variable after a call (to defer) but
-       // before popping the SP.
-       if(r->prog->as == ABL && r->nomove)
-               r = r->p1;
-
        if(LOAD(r) & ~(r->set.b[z] & ~(r->use1.b[z]|r->use2.b[z])) & bb)
                addmove(r, bn, rn, 0);