cmd/compile/internal/sparc64: fix excludedregs

Fixes golang#5

Change-Id: Ic75d3ee42fb21e9361a4cc907859d15ddabcb5e8

Author: 4ad

TODO

@@ -17,12 +17,6 @@ cd tmp && GOOS=solaris GOARCH=sparc64 go tool compile -S cmp.go
 cd tmp && GOOS=solaris GOARCH=sparc64 go tool compile -S shift.go
 cd /tmp && lsr /Users/aram/go/test | grep \.go$ | xargs egrep -L 'ERROR' | xargs egrep -L 'import' | GOOS=solaris GOARCH=sparc64 xargs -n1 go tool compile >/tmp/errors
 
-==
-
-ZR is used as a destination register
-
-==
-
 !!!
 NO DYNAMIC SIZED INSTRUCTIONS
 !!!

src/cmd/compile/internal/sparc64/reg.go

@@ -113,15 +113,15 @@ func regnames(n *int) []string {
 
 func excludedregs() uint64 {
 	// Exclude registers with fixed functions
-	regbits := RtoB(sparc64.REG_RSP) | RtoB(sparc64.REG_LR) | RtoB(sparc64.REG_GOT)
+	regbits := RtoB(sparc64.REG_ZR) | RtoB(sparc64.REG_RSP) | RtoB(sparc64.REG_LR) | RtoB(sparc64.REG_GOT)
 
 	// Exclude R26 - R31.
 	for r := sparc64.REG_MAX + 1; r <= sparc64.REG_R31; r++ {
 		regbits |= RtoB(r)
 	}
 
 	// Exclude floating point registers with fixed functions
-	regbits = RtoB(sparc64.REG_YTMP)
+	regbits |= RtoB(sparc64.REG_YTMP)
 
 	// Exclude Y16-Y31, since they don't exist.
 	for r := sparc64.REG_Y15 + 1; r <= (sparc64.REG_Y0 + 31); r++ {