cmd/internal/obj: add IsAsm flag

This allows more exciting changes to compiler-generated assembly language that might not be correct for tricky hand-crafted assembly (e.g., nop padding breaking tables of call or branch instructions). Updates #35881 Change-Id: I842b811796076c160180a364564f2844604df3fb Reviewed-on: https://go-review.googlesource.com/c/go/+/229708 Run-TryBot: David Chase <[email protected]> TryBot-Result: Gobot Gobot <[email protected]> Reviewed-by: Cherry Zhang <[email protected]>
golang · Apr 24, 2020 · f5fcc9b · f5fcc9b
1 parent 6677a2a
commit f5fcc9b
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Showing 2 changed files with 3 additions and 1 deletion.
diff --git a/src/cmd/asm/main.go b/src/cmd/asm/main.go
@@ -41,6 +41,7 @@ func main() {
 	ctxt.Flag_dynlink = *flags.Dynlink
 	ctxt.Flag_shared = *flags.Shared || *flags.Dynlink
 	ctxt.Flag_go115newobj = *flags.Go115Newobj
+	ctxt.IsAsm = true
 	switch *flags.Spectre {
 	default:
 		log.Printf("unknown setting -spectre=%s", *flags.Spectre)

diff --git a/src/cmd/internal/obj/link.go b/src/cmd/internal/obj/link.go
@@ -675,7 +675,8 @@ type Link struct {
 
 	InParallel           bool // parallel backend phase in effect
 	Framepointer_enabled bool
-	UseBASEntries        bool // Use Base Address Selection Entries in location lists and PC ranges
+	UseBASEntries        bool // use Base Address Selection Entries in location lists and PC ranges
+	IsAsm                bool // is the source assembly language, which may contain surprising idioms (e.g., call tables)
 
 	// state for writing objects
 	Text []*LSym