runtime: check consistency of all module data objects

Current code just checks the consistency (that the functab is correctly
sorted by PC, etc) of the moduledata object that the runtime belongs to.
Change to check all of them.

Change-Id: I544a44c5de7445fff87d3cdb4840ff04c5e2bf75
Reviewed-on: https://go-review.googlesource.com/9773Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

src/runtime/proc1.go

@@ -51,7 +51,7 @@ func schedinit() {
 	framepointer_enabled = haveexperiment("framepointer")
 
 	tracebackinit()
-	symtabverify()
+	moduledataverify()
 	stackinit()
 	mallocinit()
 	mcommoninit(_g_.m)

src/runtime/symtab.go

@@ -84,38 +84,44 @@ type findfuncbucket struct {
 	subbuckets [16]byte
 }
 
-func symtabverify() {
+func moduledataverify() {
+	for datap := &firstmoduledata; datap != nil; datap = datap.next {
+		moduledataverify1(datap)
+	}
+}
+
+func moduledataverify1(datap *moduledata) {
 	// See golang.org/s/go12symtab for header: 0xfffffffb,
 	// two zero bytes, a byte giving the PC quantum,
 	// and a byte giving the pointer width in bytes.
-	pcln := *(**[8]byte)(unsafe.Pointer(&firstmoduledata.pclntable))
-	pcln32 := *(**[2]uint32)(unsafe.Pointer(&firstmoduledata.pclntable))
+	pcln := *(**[8]byte)(unsafe.Pointer(&datap.pclntable))
+	pcln32 := *(**[2]uint32)(unsafe.Pointer(&datap.pclntable))
 	if pcln32[0] != 0xfffffffb || pcln[4] != 0 || pcln[5] != 0 || pcln[6] != _PCQuantum || pcln[7] != ptrSize {
 		println("runtime: function symbol table header:", hex(pcln32[0]), hex(pcln[4]), hex(pcln[5]), hex(pcln[6]), hex(pcln[7]))
 		throw("invalid function symbol table\n")
 	}
 
 	// ftab is lookup table for function by program counter.
-	nftab := len(firstmoduledata.ftab) - 1
+	nftab := len(datap.ftab) - 1
 	for i := 0; i < nftab; i++ {
 		// NOTE: ftab[nftab].entry is legal; it is the address beyond the final function.
-		if firstmoduledata.ftab[i].entry > firstmoduledata.ftab[i+1].entry {
-			f1 := (*_func)(unsafe.Pointer(&firstmoduledata.pclntable[firstmoduledata.ftab[i].funcoff]))
-			f2 := (*_func)(unsafe.Pointer(&firstmoduledata.pclntable[firstmoduledata.ftab[i+1].funcoff]))
+		if datap.ftab[i].entry > datap.ftab[i+1].entry {
+			f1 := (*_func)(unsafe.Pointer(&datap.pclntable[datap.ftab[i].funcoff]))
+			f2 := (*_func)(unsafe.Pointer(&datap.pclntable[datap.ftab[i+1].funcoff]))
 			f2name := "end"
 			if i+1 < nftab {
 				f2name = funcname(f2)
 			}
-			println("function symbol table not sorted by program counter:", hex(firstmoduledata.ftab[i].entry), funcname(f1), ">", hex(firstmoduledata.ftab[i+1].entry), f2name)
+			println("function symbol table not sorted by program counter:", hex(datap.ftab[i].entry), funcname(f1), ">", hex(datap.ftab[i+1].entry), f2name)
 			for j := 0; j <= i; j++ {
-				print("\t", hex(firstmoduledata.ftab[j].entry), " ", funcname((*_func)(unsafe.Pointer(&firstmoduledata.pclntable[firstmoduledata.ftab[j].funcoff]))), "\n")
+				print("\t", hex(datap.ftab[j].entry), " ", funcname((*_func)(unsafe.Pointer(&datap.pclntable[datap.ftab[j].funcoff]))), "\n")
 			}
 			throw("invalid runtime symbol table")
 		}
 	}
 
-	if firstmoduledata.minpc != firstmoduledata.ftab[0].entry ||
-		firstmoduledata.maxpc != firstmoduledata.ftab[nftab].entry {
+	if datap.minpc != datap.ftab[0].entry ||
+		datap.maxpc != datap.ftab[nftab].entry {
 		throw("minpc or maxpc invalid")
 	}
 }