Modified: trunk/Source/_javascript_Core/ChangeLog (281719 => 281720)
--- trunk/Source/_javascript_Core/ChangeLog 2021-08-27 21:00:39 UTC (rev 281719)
+++ trunk/Source/_javascript_Core/ChangeLog 2021-08-27 21:16:21 UTC (rev 281720)
@@ -1,5 +1,17 @@
2021-08-27 Mark Lam <mark....@apple.com>
+ Changed ARM64 probe trampoline to do ptr auth the standard way.
+ https://bugs.webkit.org/show_bug.cgi?id=229629
+ rdar://problem/82453220
+
+ Reviewed by Saam Barati.
+
+ Also fix a comment, and add back 2 lines that I accidentally deleted in r281718.
+
+ * assembler/MacroAssemblerARM64.cpp:
+
+2021-08-27 Mark Lam <mark....@apple.com>
+
Make ARM64 and X86_64 probe code a little bit more efficient.
https://bugs.webkit.org/show_bug.cgi?id=229618
rdar://82445743
Modified: trunk/Source/_javascript_Core/assembler/MacroAssemblerARM64.cpp (281719 => 281720)
--- trunk/Source/_javascript_Core/assembler/MacroAssemblerARM64.cpp 2021-08-27 21:00:39 UTC (rev 281719)
+++ trunk/Source/_javascript_Core/assembler/MacroAssemblerARM64.cpp 2021-08-27 21:16:21 UTC (rev 281720)
@@ -500,7 +500,7 @@
// returns. So, the ARM64 probe implementation will allow the probe handler to
// either modify lr or pc, but not both in the same probe invocation. The probe
// mechanism ensures that we never try to modify both lr and pc with a RELEASE_ASSERT
- // in Probe::().
+ // in Probe::executeJSCJITProbe().
// Determine if the probe handler changed the pc.
"ldr x30, [sp, #" STRINGIZE_VALUE_OF(PROBE_CPU_SP_OFFSET) "]" "\n" // preload the target sp.
@@ -521,10 +521,12 @@
#if CPU(ARM64E)
"movz x28, #" STRINGIZE_VALUE_OF(JIT_PROBE_PC_PTR_TAG) "\n"
"autib x27, x28" "\n"
- "lsr x28, x27, #8" "\n"
- "and x28, x28, #0xff000000000000" "\n"
- "orr x28, x28, x27" "\n"
- "ldrb w28, [x28]" "\n"
+ "mov x28, x27" "\n"
+ "xpaci x28" "\n"
+ "cmp x28, x27" "\n"
+ "beq " LOCAL_LABEL_STRING(ctiMasmProbeTrampolinePCAuthDone) "\n"
+ "brk #0xc471" "\n"
+ LOCAL_LABEL_STRING(ctiMasmProbeTrampolinePCAuthDone) ":" "\n"
#endif
"sub x27, x27, #" STRINGIZE_VALUE_OF(2 * GPREG_SIZE) "\n" // The return point PC is at 2 instructions before the end of the probe.
#if CPU(ARM64E)
@@ -546,10 +548,14 @@
#if CPU(ARM64E)
"movz x27, #" STRINGIZE_VALUE_OF(JIT_PROBE_PC_PTR_TAG) "\n"
"autib x28, x27" "\n"
- "lsr x27, x28, #8" "\n"
- "and x27, x27, #0xff000000000000" "\n"
- "orr x27, x27, x28" "\n"
- "ldrb w27, [x27]" "\n"
+ "mov x27, x28" "\n"
+ "xpaci x27" "\n"
+ "cmp x27, x28" "\n"
+ "beq " LOCAL_LABEL_STRING(ctiMasmProbeTrampolinePCAuthDone2) "\n"
+ "brk #0xc471" "\n"
+ LOCAL_LABEL_STRING(ctiMasmProbeTrampolinePCAuthDone2) ":" "\n"
+ "add x27, x30, #48" "\n" // Compute sp at return point.
+ "pacib x28, x27" "\n"
#endif
"ldr x27, [sp, #" STRINGIZE_VALUE_OF(PROBE_CPU_FP_OFFSET) "]" "\n"
"stp x27, x28, [x30, #" STRINGIZE_VALUE_OF(OUT_FP_OFFSET) "]" "\n"
