compiler: improve name mangling for packpaths

    
    The current implementation of Gogo::pkgpath_for_symbol was written in
    a way that allowed two distinct package paths to map to the same
    symbol, which could cause collisions at link- time or compile-time.
    
    Switch to a better mangling scheme to insure that we get a unique
    packagepath symbol for each package. In the new scheme instead of having
    separate mangling schemes for identifiers and package paths, the
    main identifier mangler ("go_encode_id") now handles mangling of
    both packagepath characters and identifier characters.
    
    The new mangling scheme is more intrusive: "foo/bar.Baz" is mangled as
    "foo..z2fbar.Baz" instead of "foo_bar.Baz". To mitigate this, this
    patch also adds a demangling capability so that function names
    returned from runtime.CallersFrames are converted back to their
    original unmangled form.
    
    Changing the pkgpath_for_symbol scheme requires updating a number of
    //go:linkname directives and C "__asm__" directives to match the new
    scheme, as well as updating the 'gotest' driver (which makes
    assumptions about the correct mapping from pkgpath symbol to package
    name).
    
    Fixes golang/go#27534.
    
    Reviewed-on: https://go-review.googlesource.com/c/135455

From-SVN: r265510

1 files changed, 26 insertions, 26 deletions

diff --git a/libgo/go/sync/atomic/atomic.c b/libgo/go/sync/atomic/atomic.c
index 07a4306..6cc730f 100644
--- a/libgo/go/sync/atomic/atomic.c
+++ b/libgo/go/sync/atomic/atomic.c
@@ -9,7 +9,7 @@
 #include "runtime.h"
 
 int32_t SwapInt32 (int32_t *, int32_t)
-  __asm__ (GOSYM_PREFIX "sync_atomic.SwapInt32")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.SwapInt32")
   __attribute__ ((no_split_stack));
 
 int32_t
@@ -19,7 +19,7 @@ SwapInt32 (int32_t *addr, int32_t new)
 }
 
 int64_t SwapInt64 (int64_t *, int64_t)
-  __asm__ (GOSYM_PREFIX "sync_atomic.SwapInt64")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.SwapInt64")
   __attribute__ ((no_split_stack));
 
 int64_t
@@ -31,7 +31,7 @@ SwapInt64 (int64_t *addr, int64_t new)
 }
 
 uint32_t SwapUint32 (uint32_t *, uint32_t)
-  __asm__ (GOSYM_PREFIX "sync_atomic.SwapUint32")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.SwapUint32")
   __attribute__ ((no_split_stack));
 
 uint32_t
@@ -41,7 +41,7 @@ SwapUint32 (uint32_t *addr, uint32_t new)
 }
 
 uint64_t SwapUint64 (uint64_t *, uint64_t)
-  __asm__ (GOSYM_PREFIX "sync_atomic.SwapUint64")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.SwapUint64")
   __attribute__ ((no_split_stack));
 
 uint64_t
@@ -53,7 +53,7 @@ SwapUint64 (uint64_t *addr, uint64_t new)
 }
 
 uintptr_t SwapUintptr (uintptr_t *, uintptr_t)
-  __asm__ (GOSYM_PREFIX "sync_atomic.SwapUintptr")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.SwapUintptr")
   __attribute__ ((no_split_stack));
 
 uintptr_t
@@ -63,7 +63,7 @@ SwapUintptr (uintptr_t *addr, uintptr_t new)
 }
 
 _Bool CompareAndSwapInt32 (int32_t *, int32_t, int32_t)
-  __asm__ (GOSYM_PREFIX "sync_atomic.CompareAndSwapInt32")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.CompareAndSwapInt32")
   __attribute__ ((no_split_stack));
 
 _Bool
@@ -73,7 +73,7 @@ CompareAndSwapInt32 (int32_t *val, int32_t old, int32_t new)
 }
 
 _Bool CompareAndSwapInt64 (int64_t *, int64_t, int64_t)
-  __asm__ (GOSYM_PREFIX "sync_atomic.CompareAndSwapInt64")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.CompareAndSwapInt64")
   __attribute__ ((no_split_stack));
 
 _Bool
@@ -85,7 +85,7 @@ CompareAndSwapInt64 (int64_t *val, int64_t old, int64_t new)
 }
 
 _Bool CompareAndSwapUint32 (uint32_t *, uint32_t, uint32_t)
-  __asm__ (GOSYM_PREFIX "sync_atomic.CompareAndSwapUint32")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.CompareAndSwapUint32")
   __attribute__ ((no_split_stack));
 
 _Bool
@@ -95,7 +95,7 @@ CompareAndSwapUint32 (uint32_t *val, uint32_t old, uint32_t new)
 }
 
 _Bool CompareAndSwapUint64 (uint64_t *, uint64_t, uint64_t)
-  __asm__ (GOSYM_PREFIX "sync_atomic.CompareAndSwapUint64")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.CompareAndSwapUint64")
   __attribute__ ((no_split_stack));
 
 _Bool
@@ -107,7 +107,7 @@ CompareAndSwapUint64 (uint64_t *val, uint64_t old, uint64_t new)
 }
 
 _Bool CompareAndSwapUintptr (uintptr_t *, uintptr_t, uintptr_t)
-  __asm__ (GOSYM_PREFIX "sync_atomic.CompareAndSwapUintptr")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.CompareAndSwapUintptr")
   __attribute__ ((no_split_stack));
 
 _Bool
@@ -117,7 +117,7 @@ CompareAndSwapUintptr (uintptr_t *val, uintptr_t old, uintptr_t new)
 }
 
 int32_t AddInt32 (int32_t *, int32_t)
-  __asm__ (GOSYM_PREFIX "sync_atomic.AddInt32")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.AddInt32")
   __attribute__ ((no_split_stack));
 
 int32_t
@@ -127,7 +127,7 @@ AddInt32 (int32_t *val, int32_t delta)
 }
 
 uint32_t AddUint32 (uint32_t *, uint32_t)
-  __asm__ (GOSYM_PREFIX "sync_atomic.AddUint32")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.AddUint32")
   __attribute__ ((no_split_stack));
 
 uint32_t
@@ -137,7 +137,7 @@ AddUint32 (uint32_t *val, uint32_t delta)
 }
 
 int64_t AddInt64 (int64_t *, int64_t)
-  __asm__ (GOSYM_PREFIX "sync_atomic.AddInt64")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.AddInt64")
   __attribute__ ((no_split_stack));
 
 int64_t
@@ -149,7 +149,7 @@ AddInt64 (int64_t *val, int64_t delta)
 }
 
 uint64_t AddUint64 (uint64_t *, uint64_t)
-  __asm__ (GOSYM_PREFIX "sync_atomic.AddUint64")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.AddUint64")
   __attribute__ ((no_split_stack));
 
 uint64_t
@@ -161,7 +161,7 @@ AddUint64 (uint64_t *val, uint64_t delta)
 }
 
 uintptr_t AddUintptr (uintptr_t *, uintptr_t)
-  __asm__ (GOSYM_PREFIX "sync_atomic.AddUintptr")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.AddUintptr")
   __attribute__ ((no_split_stack));
 
 uintptr_t
@@ -171,7 +171,7 @@ AddUintptr (uintptr_t *val, uintptr_t delta)
 }
 
 int32_t LoadInt32 (int32_t *addr)
-  __asm__ (GOSYM_PREFIX "sync_atomic.LoadInt32")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.LoadInt32")
   __attribute__ ((no_split_stack));
 
 int32_t
@@ -186,7 +186,7 @@ LoadInt32 (int32_t *addr)
 }
 
 int64_t LoadInt64 (int64_t *addr)
-  __asm__ (GOSYM_PREFIX "sync_atomic.LoadInt64")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.LoadInt64")
   __attribute__ ((no_split_stack));
 
 int64_t
@@ -203,7 +203,7 @@ LoadInt64 (int64_t *addr)
 }
 
 uint32_t LoadUint32 (uint32_t *addr)
-  __asm__ (GOSYM_PREFIX "sync_atomic.LoadUint32")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.LoadUint32")
   __attribute__ ((no_split_stack));
 
 uint32_t
@@ -218,7 +218,7 @@ LoadUint32 (uint32_t *addr)
 }
 
 uint64_t LoadUint64 (uint64_t *addr)
-  __asm__ (GOSYM_PREFIX "sync_atomic.LoadUint64")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.LoadUint64")
   __attribute__ ((no_split_stack));
 
 uint64_t
@@ -235,7 +235,7 @@ LoadUint64 (uint64_t *addr)
 }
 
 uintptr_t LoadUintptr (uintptr_t *addr)
-  __asm__ (GOSYM_PREFIX "sync_atomic.LoadUintptr")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.LoadUintptr")
   __attribute__ ((no_split_stack));
 
 uintptr_t
@@ -250,7 +250,7 @@ LoadUintptr (uintptr_t *addr)
 }
 
 void *LoadPointer (void **addr)
-  __asm__ (GOSYM_PREFIX "sync_atomic.LoadPointer")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.LoadPointer")
   __attribute__ ((no_split_stack));
 
 void *
@@ -265,7 +265,7 @@ LoadPointer (void **addr)
 }
 
 void StoreInt32 (int32_t *addr, int32_t val)
-  __asm__ (GOSYM_PREFIX "sync_atomic.StoreInt32")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.StoreInt32")
   __attribute__ ((no_split_stack));
 
 void
@@ -279,7 +279,7 @@ StoreInt32 (int32_t *addr, int32_t val)
 }
 
 void StoreInt64 (int64_t *addr, int64_t val)
-  __asm__ (GOSYM_PREFIX "sync_atomic.StoreInt64")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.StoreInt64")
   __attribute__ ((no_split_stack));
 
 void
@@ -295,7 +295,7 @@ StoreInt64 (int64_t *addr, int64_t val)
 }
 
 void StoreUint32 (uint32_t *addr, uint32_t val)
-  __asm__ (GOSYM_PREFIX "sync_atomic.StoreUint32")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.StoreUint32")
   __attribute__ ((no_split_stack));
 
 void
@@ -309,7 +309,7 @@ StoreUint32 (uint32_t *addr, uint32_t val)
 }
 
 void StoreUint64 (uint64_t *addr, uint64_t val)
-  __asm__ (GOSYM_PREFIX "sync_atomic.StoreUint64")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.StoreUint64")
   __attribute__ ((no_split_stack));
 
 void
@@ -325,7 +325,7 @@ StoreUint64 (uint64_t *addr, uint64_t val)
 }
 
 void StoreUintptr (uintptr_t *addr, uintptr_t val)
-  __asm__ (GOSYM_PREFIX "sync_atomic.StoreUintptr")
+  __asm__ (GOSYM_PREFIX "sync..z2fatomic.StoreUintptr")
   __attribute__ ((no_split_stack));
 
 void