cmd/compile, cmd/link: FIPS fixes for large programs

1. In cmd/internal/obj, only apply the exclusion list to data symbols.
   Text symbols are always fine since they can use PC-relative relocations.

2. In cmd/link, only skip trampolines for text symbols in the same package
   with the same type. Before, all text symbols had type STEXT, but now that
   there are different sections of STEXT, we can only rely on symbols in the
   same package in the same section being close enough not to need
   trampolines.

Fixes #70379.

Change-Id: Ifad2bdd6001ad3b5b23e641127554e9ec374715e
Reviewed-on: https://go-review.googlesource.com/c/go/+/631036
Auto-Submit: Russ Cox <rsc@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

6 files changed, 9 insertions, 11 deletions

diff --git a/src/cmd/link/internal/arm/asm.go b/src/cmd/link/internal/arm/asm.go
index 7fd0a99c75..ab816c7015 100644
--- a/src/cmd/link/internal/arm/asm.go
+++ b/src/cmd/link/internal/arm/asm.go
@@ -455,7 +455,7 @@ func trampoline(ctxt *ld.Link, ldr *loader.Loader, ri int, rs, s loader.Sym) {
 			if ldr.SymType(tramp) == 0 {
 				// trampoline does not exist, create one
 				trampb := ldr.MakeSymbolUpdater(tramp)
-				ctxt.AddTramp(trampb)
+				ctxt.AddTramp(trampb, ldr.SymType(s))
 				if ctxt.DynlinkingGo() || ldr.SymType(rs) == sym.SDYNIMPORT {
 					if immrot(uint32(offset)) == 0 {
 						ctxt.Errorf(s, "odd offset in dynlink direct call: %v+%d", ldr.SymName(rs), offset)
diff --git a/src/cmd/link/internal/arm64/asm.go b/src/cmd/link/internal/arm64/asm.go
index 4ec4b65793..68474b4484 100644
--- a/src/cmd/link/internal/arm64/asm.go
+++ b/src/cmd/link/internal/arm64/asm.go
@@ -1365,7 +1365,7 @@ func trampoline(ctxt *ld.Link, ldr *loader.Loader, ri int, rs, s loader.Sym) {
 			if ldr.SymType(tramp) == 0 {
 				// trampoline does not exist, create one
 				trampb := ldr.MakeSymbolUpdater(tramp)
-				ctxt.AddTramp(trampb)
+				ctxt.AddTramp(trampb, ldr.SymType(s))
 				if ldr.SymType(rs) == sym.SDYNIMPORT {
 					if r.Add() != 0 {
 						ctxt.Errorf(s, "nonzero addend for DYNIMPORT call: %v+%d", ldr.SymName(rs), r.Add())
diff --git a/src/cmd/link/internal/ld/data.go b/src/cmd/link/internal/ld/data.go
index 185e1cc36c..b6eaf69ca4 100644
--- a/src/cmd/link/internal/ld/data.go
+++ b/src/cmd/link/internal/ld/data.go
@@ -129,7 +129,7 @@ func trampoline(ctxt *Link, s loader.Sym) {
 			// don't randomize the function order).
 			// Except that if SymPkg(s) == "", it is a host object symbol
 			// which may call an external symbol via PLT.
-			if ldr.SymPkg(s) != "" && ldr.SymPkg(rs) == ldr.SymPkg(s) && *flagRandLayout == 0 {
+			if ldr.SymPkg(s) != "" && ldr.SymPkg(rs) == ldr.SymPkg(s) && ldr.SymType(rs) == ldr.SymType(s) && *flagRandLayout == 0 {
 				// RISC-V is only able to reach +/-1MiB via a JAL instruction.
 				// We need to generate a trampoline when an address is
 				// currently unknown.
@@ -1643,7 +1643,7 @@ func (ctxt *Link) dodata(symGroupType []sym.SymKind) {
 
 		st := state.symType(s)
 
-		if st <= sym.STEXT || st >= sym.SXREF {
+		if st <= sym.STEXTFIPSEND || st >= sym.SXREF {
 			continue
 		}
 		state.data[st] = append(state.data[st], s)
@@ -3127,8 +3127,8 @@ func (ctxt *Link) layout(order []*sym.Segment) uint64 {
 }
 
 // add a trampoline with symbol s (to be laid down after the current function)
-func (ctxt *Link) AddTramp(s *loader.SymbolBuilder) {
-	s.SetType(sym.STEXT)
+func (ctxt *Link) AddTramp(s *loader.SymbolBuilder, typ sym.SymKind) {
+	s.SetType(typ)
 	s.SetReachable(true)
 	s.SetOnList(true)
 	ctxt.tramps = append(ctxt.tramps, s.Sym())
diff --git a/src/cmd/link/internal/loong64/asm.go b/src/cmd/link/internal/loong64/asm.go
index 7d1c8df6ed..2e69594f92 100644
--- a/src/cmd/link/internal/loong64/asm.go
+++ b/src/cmd/link/internal/loong64/asm.go
@@ -308,7 +308,7 @@ func trampoline(ctxt *ld.Link, ldr *loader.Loader, ri int, rs, s loader.Sym) {
 			if ldr.SymType(tramp) == 0 {
 				// trampoline does not exist, create one
 				trampb := ldr.MakeSymbolUpdater(tramp)
-				ctxt.AddTramp(trampb)
+				ctxt.AddTramp(trampb, ldr.SymType(s))
 				if ldr.SymType(rs) == sym.SDYNIMPORT {
 					if r.Add() != 0 {
 						ctxt.Errorf(s, "nonzero addend for DYNIMPORT call: %v+%d", ldr.SymName(rs), r.Add())
diff --git a/src/cmd/link/internal/ppc64/asm.go b/src/cmd/link/internal/ppc64/asm.go
index 94660beba8..af7cddff7f 100644
--- a/src/cmd/link/internal/ppc64/asm.go
+++ b/src/cmd/link/internal/ppc64/asm.go
@@ -1189,9 +1189,7 @@ func trampoline(ctxt *ld.Link, ldr *loader.Loader, ri int, rs, s loader.Sym) {
 	}
 	switch r.Type() {
 	case objabi.R_CALLPOWER:
-
 		// If branch offset is too far then create a trampoline.
-
 		if (ctxt.IsExternal() && ldr.SymSect(s) != ldr.SymSect(rs)) || (ctxt.IsInternal() && int64(int32(t<<6)>>6) != t) || ldr.SymValue(rs) == 0 || (*ld.FlagDebugTramp > 1 && ldr.SymPkg(s) != ldr.SymPkg(rs)) {
 			var tramp loader.Sym
 			for i := 0; ; i++ {
@@ -1229,7 +1227,7 @@ func trampoline(ctxt *ld.Link, ldr *loader.Loader, ri int, rs, s loader.Sym) {
 			}
 			if ldr.SymType(tramp) == 0 {
 				trampb := ldr.MakeSymbolUpdater(tramp)
-				ctxt.AddTramp(trampb)
+				ctxt.AddTramp(trampb, ldr.SymType(s))
 				gentramp(ctxt, ldr, trampb, rs, r.Add())
 			}
 			sb := ldr.MakeSymbolUpdater(s)
diff --git a/src/cmd/link/internal/riscv64/asm.go b/src/cmd/link/internal/riscv64/asm.go
index 587b10f512..a3f50dc54f 100644
--- a/src/cmd/link/internal/riscv64/asm.go
+++ b/src/cmd/link/internal/riscv64/asm.go
@@ -682,7 +682,7 @@ func trampoline(ctxt *ld.Link, ldr *loader.Loader, ri int, rs, s loader.Sym) {
 		}
 		if ldr.SymType(tramp) == 0 {
 			trampb := ldr.MakeSymbolUpdater(tramp)
-			ctxt.AddTramp(trampb)
+			ctxt.AddTramp(trampb, ldr.SymType(s))
 			genCallTramp(ctxt.Arch, ctxt.LinkMode, ldr, trampb, rs, int64(r.Add()))
 		}
 		sb := ldr.MakeSymbolUpdater(s)