target/alpha: Document gdbstub register indexes
Follow GDB XML comments. Re-order switch cases for clarity. Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org> Message-ID: <20260219191955.83815-6-philmd@linaro.org>
Philippe Mathieu-Daudé committed
Feb 17, 2026 at 08:29 UTC
e4eff9dfaad4ccf9d0241825e11747263d026224
1 file changed
+12
-13
target/alpha/gdbstub.c
+12
-13
@@ -31,6 +31,9 @@ int alpha_cpu_gdb_read_register(CPUState *cs, GByteArray *mem_buf, int n)
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case 0 ... 30:
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val = cpu_alpha_load_gr(env, n);
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break;
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+ case 31: /* zero register */
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+ val = 0;
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+ break;
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case 32 ... 62:
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d.d = env->fir[n - 32];
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val = d.ll;
@@ -41,15 +44,12 @@ int alpha_cpu_gdb_read_register(CPUState *cs, GByteArray *mem_buf, int n)
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case 64:
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val = env->pc;
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break;
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- case 66:
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- val = env->unique;
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- break;
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- case 31:
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- case 65:
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- /* 31 really is the zero register; 65 is unassigned in the
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- gdb protocol, but is still required to occupy 8 bytes. */
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+ case 65: /* former Virtual Register (reserved as unassigned) */
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val = 0;
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break;
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+ case 66: /* PALcode Memory Slot */
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+ val = env->unique;
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+ break;
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default:
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return 0;
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}
@@ -66,6 +66,8 @@ int alpha_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n)
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case 0 ... 30:
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cpu_alpha_store_gr(env, n, tmp);
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break;
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+ case 31: /* zero register */
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+ break;
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case 32 ... 62:
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d.ll = tmp;
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env->fir[n - 32] = d.d;
@@ -76,13 +78,10 @@ int alpha_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n)
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case 64:
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env->pc = tmp;
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break;
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- case 66:
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- env->unique = tmp;
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+ case 65: /* former Virtual Register (reserved as unassigned) */
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break;
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- case 31:
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- case 65:
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- /* 31 really is the zero register; 65 is unassigned in the
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- gdb protocol, but is still required to occupy 8 bytes. */
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+ case 66: /* PALcode Memory Slot */
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+ env->unique = tmp;
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break;
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default:
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return 0;