target/arm: Fix non-TCG build failure by inlining pauth_ptr_mask()

aarch64_gdb_get_pauth_reg() -- although disabled since commit
5787d17a42 ("target/arm: Don't advertise aarch64-pauth.xml to
gdb") is still compiled in. It calls pauth_ptr_mask() which is
located in target/arm/tcg/pauth_helper.c, a TCG specific helper.

To avoid a linking error when TCG is not enabled:

  Undefined symbols for architecture arm64:
    "_pauth_ptr_mask", referenced from:
        _aarch64_gdb_get_pauth_reg in target_arm_gdbstub64.c.o
  ld: symbol(s) not found for architecture arm64
  clang: error: linker command failed with exit code 1 (use -v to see invocation)

- Inline pauth_ptr_mask() in aarch64_gdb_get_pauth_reg()
  (this is the single user),
- Rename pauth_ptr_mask_internal() as pauth_ptr_mask() and
  inline it in "internals.h",

Fixes: e995d5cce4 ("target/arm: Implement gdbstub pauth extension")
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20230328212516.29592-1-philmd@linaro.org
[PMM: reinstated doc comment]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

target/arm/gdbstub64.c

@@ -230,8 +230,11 @@ int aarch64_gdb_get_pauth_reg(CPUARMState *env, GByteArray *buf, int reg)
         {
             bool is_data = !(reg & 1);
             bool is_high = reg & 2;
-            uint64_t mask = pauth_ptr_mask(env, -is_high, is_data);
+            ARMMMUIdx mmu_idx = arm_stage1_mmu_idx(env);
-            return gdb_get_reg64(buf, mask);
+            ARMVAParameters param;
+
+            param = aa64_va_parameters(env, -is_high, mmu_idx, is_data);
+            return gdb_get_reg64(buf, pauth_ptr_mask(param));
         }
     default:
         return 0;

target/arm/internals.h

@@ -1391,13 +1391,18 @@ bool arm_generate_debug_exceptions(CPUARMState *env);
 
 /**
  * pauth_ptr_mask:
- * @env: cpu context
+ * @param: parameters defining the MMU setup
- * @ptr: selects between TTBR0 and TTBR1
- * @data: selects between TBI and TBID
  *
- * Return a mask of the bits of @ptr that contain the authentication code.
+ * Return a mask of the address bits that contain the authentication code,
+ * given the MMU config defined by @param.
  */
-uint64_t pauth_ptr_mask(CPUARMState *env, uint64_t ptr, bool data);
+static inline uint64_t pauth_ptr_mask(ARMVAParameters param)
+{
+    int bot_pac_bit = 64 - param.tsz;
+    int top_pac_bit = 64 - 8 * param.tbi;
+
+    return MAKE_64BIT_MASK(bot_pac_bit, top_pac_bit - bot_pac_bit);
+}
 
 /* Add the cpreg definitions for debug related system registers */
 void define_debug_regs(ARMCPU *cpu);

target/arm/tcg/pauth_helper.c

@@ -339,17 +339,9 @@ static uint64_t pauth_addpac(CPUARMState *env, uint64_t ptr, uint64_t modifier,
     return pac | ext | ptr;
 }
 
-static uint64_t pauth_ptr_mask_internal(ARMVAParameters param)
-{
-    int bot_pac_bit = 64 - param.tsz;
-    int top_pac_bit = 64 - 8 * param.tbi;
-
-    return MAKE_64BIT_MASK(bot_pac_bit, top_pac_bit - bot_pac_bit);
-}
-
 static uint64_t pauth_original_ptr(uint64_t ptr, ARMVAParameters param)
 {
-    uint64_t mask = pauth_ptr_mask_internal(param);
+    uint64_t mask = pauth_ptr_mask(param);
 
     /* Note that bit 55 is used whether or not the regime has 2 ranges. */
     if (extract64(ptr, 55, 1)) {
@@ -359,14 +351,6 @@ static uint64_t pauth_original_ptr(uint64_t ptr, ARMVAParameters param)
     }
 }
 
-uint64_t pauth_ptr_mask(CPUARMState *env, uint64_t ptr, bool data)
-{
-    ARMMMUIdx mmu_idx = arm_stage1_mmu_idx(env);
-    ARMVAParameters param = aa64_va_parameters(env, ptr, mmu_idx, data);
-
-    return pauth_ptr_mask_internal(param);
-}
-
 static uint64_t pauth_auth(CPUARMState *env, uint64_t ptr, uint64_t modifier,
                            ARMPACKey *key, bool data, int keynumber)
 {