netdev: devicetree.resource stubs list every scratch register the call may destroy (#70, B of 3) - #72
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…l may destroy The eight devicetree.resource stubs in netdev_dtree.c passed a0 (and a1 for dt_getchild and dt_findprop) as asm inputs only. The library ABI lets every LVO destroy d0/d1/a0/a1, but GCC was told those registers survived the jsr. All eight were LATENT at main 7108650, in both images that link the file (anxgenet.device and InstallNetProbe). dt_closekey, dt_findprop, dt_proplen and dt_propvalue stay out of line and return straight after the jsr. At the inlined dt_openkey / dt_getchild / dt_getparent / dt_keyname sites, the register is rewritten or a call comes first (the per-site addresses are in #70). Each argument register is now a "+r" operand. The code is unchanged: aligned against the pre-change build, the only difference in either image is the "$VER ... 7108650-dirty" stamp of the uncommitted build. The #70 scanner no longer flags netdev_dtree.c. Part of #70 (shipped sites, PR B of 3). Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
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…call may destroy (#73) installnetprobe.c's three card.resource stubs (OwnCard, ReleaseCard, CopyTuple) passed their argument registers as asm inputs only. The library ABI lets every LVO destroy d0/d1/a0/a1. This was REAL at main 66e0bf5. probe_own_card loads a1 = &handle (0x968) for OwnCard (jsr -6 at 0x96e). On the owned path, the first CopyTuple(0x20) (jsr -72 at 0x98e) was issued without reloading a1, so it used whatever OwnCard left there. After the change, 0x986 is `lea 0x18,a1` before the CopyTuple, which reloads the handle. The other two stubs were latent. Each argument register is now a "+r" operand; unused scratch registers remain clobbers. The #70 scanner no longer flags installnetprobe.c. With #71 and #72 this closes the 16 shipped sites in #70. Part of #70 (shipped sites, PR C of 3). Co-authored-by: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
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Part of #70, shipped-site fixes, PR B of 3:
src/netdev/netdev_dtree.c→ anxgenet.device + InstallNetProbe. Independent of A (#71) and C.The eight devicetree.resource stubs passed a0 (and a1 for dt_getchild/dt_findprop) as asm inputs only. All eight were LATENT at main 7108650 in both images; the per-site evidence is in #70.
Change: each argument register becomes a
"+r"operand, with a comment at the stub block. No CHANGELOG entry: nothing user-visible changes.No code change results:
$VERcommit stamp (file 0x5ff6-0x6011, stamp at 0x6000)$VERcommit stamp (file 0xc64-0xc7f, stamp at 0xc6e)The out-of-line helpers' windows are identical (
movea.l 8(sp),a0; movea.l 0xc,a6; jsr -N(a6); movea.l (sp)+,a6; rts).Proof:
tools/ci.sh hostin CI conditions: rc 0, 464/464.🤖 Generated with Claude Code