[OR1K] Add a dedicated PC register to register state.
Before this commit, R9, the link register, was used as PC register.
However, a stack frame may have R9 not set to PC on entry, either
because it uses a custom calling convention, or, more likely,
because this is a signal or exception stack frame. Using R9 as
PC register made it impossible to unwind such frames.
All other architectures similarly use a dedicated PC register.
git-svn-id: https://llvm.org/svn/llvm-project/libunwind/trunk@332512 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/src/Registers.hpp b/src/Registers.hpp
index 3817d82..f736ded 100644
--- a/src/Registers.hpp
+++ b/src/Registers.hpp
@@ -2521,12 +2521,13 @@
uint64_t getSP() const { return _registers.__r[1]; }
void setSP(uint32_t value) { _registers.__r[1] = value; }
- uint64_t getIP() const { return _registers.__r[9]; }
- void setIP(uint32_t value) { _registers.__r[9] = value; }
+ uint64_t getIP() const { return _registers.__pc; }
+ void setIP(uint32_t value) { _registers.__pc = value; }
private:
struct or1k_thread_state_t {
- unsigned int __r[32];
+ unsigned int __r[32]; // r0-r31
+ unsigned int __pc; // Program counter
};
or1k_thread_state_t _registers;
@@ -2561,7 +2562,7 @@
switch (regNum) {
case UNW_REG_IP:
- return _registers.__r[9];
+ return _registers.__pc;
case UNW_REG_SP:
return _registers.__r[1];
}
@@ -2576,7 +2577,7 @@
switch (regNum) {
case UNW_REG_IP:
- _registers.__r[9] = value;
+ _registers.__pc = value;
return;
case UNW_REG_SP:
_registers.__r[1] = value;
diff --git a/src/UnwindRegistersRestore.S b/src/UnwindRegistersRestore.S
index e0bf61e..d425d1c 100644
--- a/src/UnwindRegistersRestore.S
+++ b/src/UnwindRegistersRestore.S
@@ -758,7 +758,7 @@
# thread_state pointer is in r3
#
- # restore integral registerrs
+ # restore integral registers
l.lwz r0, 0(r3)
l.lwz r1, 4(r3)
l.lwz r2, 8(r3)
@@ -768,7 +768,7 @@
l.lwz r6, 24(r3)
l.lwz r7, 28(r3)
l.lwz r8, 32(r3)
- l.lwz r9, 36(r3)
+ # skip r9
l.lwz r10, 40(r3)
l.lwz r11, 44(r3)
l.lwz r12, 48(r3)
@@ -795,6 +795,8 @@
# at last, restore r3
l.lwz r3, 12(r3)
+ # load new pc into ra
+ l.lwz r9, 128(r3)
# jump to pc
l.jr r9
l.nop
diff --git a/src/UnwindRegistersSave.S b/src/UnwindRegistersSave.S
index ac925d9..34f9205 100644
--- a/src/UnwindRegistersSave.S
+++ b/src/UnwindRegistersSave.S
@@ -938,6 +938,8 @@
l.sw 116(r3), r29
l.sw 120(r3), r30
l.sw 124(r3), r31
+ # store ra to pc
+ l.sw 128(r3), r9
#endif
#endif /* !defined(__USING_SJLJ_EXCEPTIONS__) */
