[dev.power64] liblink: rewrite MOVD $con(Ra), Rb into ADD $con, Ra, Rb; fix stack...

LGTM=rsc
R=rsc, iant
CC=golang-codereviews
https://golang.org/cl/129050043

diff --git a/src/liblink/obj9.c b/src/liblink/obj9.c
index 321e2c9bf4cc2a8b99c78677eeffe0e32dd9f9cc..960083bf9b9e8a85c2a9f0d1666767f8ea936e45 100644 (file)
--- a/src/liblink/obj9.c
+++ b/src/liblink/obj9.c
@@ -179,6 +179,15 @@ progedit(Link *ctxt, Prog *p)
                }
                break;
        }
+
+       if(p->from.type == D_CONST && p->from.reg != NREG) {
+               if(p->as == AMOVD && p->to.type == D_REG) {
+                       p->as = AADD;
+                       p->reg = p->from.reg;
+                       p->from.reg = NREG;
+               } else
+                       ctxt->diag("invalid instruction: %P", p);
+       }
 }
 
 static Prog*   stacksplit(Link*, Prog*, int32, int);
@@ -639,9 +648,6 @@ addstacksplit(Link *ctxt, LSym *cursym)
 static Prog*
 stacksplit(Link *ctxt, Prog *p, int32 framesize, int noctxt)
 {
-       // TODO(minux)
-       return p;
-
        int32 arg;
        Prog *q, *q1;
 
@@ -696,7 +702,7 @@ stacksplit(Link *ctxt, Prog *p, int32 framesize, int noctxt)
                //      ADD     $StackGuard, SP, R4
                //      SUB     R3, R4
                //      MOVD    $(framesize+(StackGuard-StackSmall)), R31
-               //      CMP     R4, R31
+               //      CMPU    R31, R4
                p = appendp(ctxt, p);
                p->as = ACMP;
                p->from.type = D_REG;
@@ -733,9 +739,9 @@ stacksplit(Link *ctxt, Prog *p, int32 framesize, int noctxt)
                p = appendp(ctxt, p);
                p->as = ACMPU;
                p->from.type = D_REG;
-               p->from.reg = 4;
+               p->from.reg = REGTMP;
                p->to.type = D_REG;
-               p->to.reg = REGTMP;
+               p->to.reg = 4;
        }
 
        // q1: BLT      done
@@ -762,7 +768,7 @@ stacksplit(Link *ctxt, Prog *p, int32 framesize, int noctxt)
                arg = 0;
        else if(arg == ArgsSizeUnknown)
                ctxt->diag("%s: arg size unknown, but split stack", ctxt->cursym->name);
-       if(arg&3) // ????
+       if(arg&7)
                ctxt->diag("misaligned argument size in stack split: %d", arg);
        p->from.offset = arg;
        p->to.type = D_REG;