[src/trunk]: src/sys/lib/libunwind Teach the LLVM-derived unwinder about the ...

[thorpej <thorpej%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/909270bc9444
branches:  trunk
changeset: 1026381:909270bc9444
user:      thorpej <thorpej%NetBSD.org@localhost>
date:      Sat Nov 20 19:06:21 2021 +0000

description:
Teach the LLVM-derived unwinder about the DWARF pseudo-register defined
by GCC for Alpha to hold the return address where the signal trampoline
will resume.

diffstat:

 sys/lib/libunwind/Registers.hpp |  20 +++++++++++++++-----
 1 files changed, 15 insertions(+), 5 deletions(-)

diffs (64 lines):

diff -r b854bc14f2f3 -r 909270bc9444 sys/lib/libunwind/Registers.hpp
--- a/sys/lib/libunwind/Registers.hpp   Sat Nov 20 18:19:18 2021 +0000
+++ b/sys/lib/libunwind/Registers.hpp   Sat Nov 20 19:06:21 2021 +0000
@@ -796,6 +796,7 @@
   DWARF_ALPHA_R30 = 30,
   DWARF_ALPHA_F0 = 32,
   DWARF_ALPHA_F30 = 62,
+  DWARF_ALPHA_SIGRETURN = 64,
 
   REGNO_ALPHA_R0 = 0,
   REGNO_ALPHA_R26 = 26,
@@ -803,13 +804,14 @@
   REGNO_ALPHA_PC = 31,
   REGNO_ALPHA_F0 = 32,
   REGNO_ALPHA_F30 = 62,
+  REGNO_ALPHA_SIGRETURN = 64,
 };
 
 class Registers_Alpha {
 public:
   enum {
-    LAST_REGISTER = REGNO_ALPHA_F30,
-    LAST_RESTORE_REG = REGNO_ALPHA_F30,
+    LAST_REGISTER = REGNO_ALPHA_SIGRETURN,
+    LAST_RESTORE_REG = REGNO_ALPHA_SIGRETURN,
     RETURN_OFFSET = 0,
     RETURN_MASK = 0,
   };
@@ -820,17 +822,24 @@
   static int dwarf2regno(int num) { return num; }
 
   bool validRegister(int num) const {
-    return num >= 0 && num <= REGNO_ALPHA_PC;
+    return (num >= 0 && num <= REGNO_ALPHA_PC) ||
+       num == REGNO_ALPHA_SIGRETURN;
   }
 
   uint64_t getRegister(int num) const {
     assert(validRegister(num));
-    return reg[num];
+    if (num == REGNO_ALPHA_SIGRETURN)
+      return sigreturn_reg;
+    else
+      return reg[num];
   }
 
   void setRegister(int num, uint64_t value) {
     assert(validRegister(num));
-    reg[num] = value;
+    if (num == REGNO_ALPHA_SIGRETURN)
+      sigreturn_reg = value;
+    else
+      reg[num] = value;
   }
 
   uint64_t getIP() const { return reg[REGNO_ALPHA_PC]; }
@@ -856,6 +865,7 @@
 private:
   uint64_t reg[REGNO_ALPHA_PC + 1];
   uint64_t fpreg[31];
+  uint64_t sigreturn_reg;
 };
 
 enum {