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ZJIT: Load stack relative slot before frame teardown#13953

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ZJIT: Load stack relative slot before frame teardown#13953

XrXr wants to merge1 commit intoruby:masterfromShopify:zjit-load-before-frame-teardown

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XrXr commentedJul 18, 2025

Or else the test returns garbage since it loads after
moving SP. Prior bad disassembly:

# Block: bb0(v0, v1, v2, v3, v4, v5, v6, v7, v8)stp x29, x30, [sp, #-0x10]!mov x29, sp# bump C stack pointersub sp, sp, #0x10# Insn: v10 Return v8# pop stack frameadds x19, x19, #0x38stur x19, [x20, #0x10]# restore C stack pointeradd sp, sp, #0x10mov sp, x29ldp x29, x30, [sp], #0x10ldur x0, [sp]ret

ZJIT: Load stack relative slot before frame teardown

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Or else the test returns garbage since it loads aftermoving SP. Prior bad disassembly:    # Block: bb0(v0, v1, v2, v3, v4, v5, v6, v7, v8)    stp x29, x30, [sp, #-0x10]!    mov x29, sp    # bump C stack pointer    sub sp, sp, #0x10    # Insn: v10 Return v8    # pop stack frame    adds x19, x19, #0x38    stur x19, [x20, #0x10]    # restore C stack pointer    add sp, sp, #0x10    mov sp, x29    ldp x29, x30, [sp], #0x10    ldur x0, [sp]    ret