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@llvm/pr-subscribers-libunwind

Author: Jade Marker (Jade-Marker)

diff --git a/libunwind/src/UnwindRegistersRestore.S b/libunwind/src/UnwindRegistersRestore.S
index 5e199188945df..2b1593b16754e 100644
--- a/libunwind/src/UnwindRegistersRestore.S
+++ b/libunwind/src/UnwindRegistersRestore.S
@@ -1044,9 +1044,10 @@ DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind18Registers_mips_o326jumptoEv)
   lw    $27, (4 * 27)($4)
   lw    $28, (4 * 28)($4)
   lw    $29, (4 * 29)($4)
-  lw    $30, (4 * 30)($4)
   // load new pc into ra
   lw    $31, (4 * 32)($4)
+  //allow for load delay, so that ra address is new value when jumping
+  lw    $30, (4 * 30)($4)
   // jump to ra, load a0 in the delay slot
   jr    $31
   lw    $4, (4 * 4)($4)
@@ -1082,11 +1083,13 @@ DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind21Registers_mips_newabi6jumptoEv)
   ld    $2, (8 * 2)($4)
   ld    $3, (8 * 3)($4)
   // skip a0 for now
-  .irp i,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30
+  .irp i,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29
     ld $\i, (8 * \i)($4)
   .endr
   // load new pc into ra
-  ld    $31, (8 * 32)($4)
+  ld    $31, (4 * 32)($4)
+  //allow for load delay, so that ra address is new value when jumping
+  ld    $30, (4 * 30)($4)
   // jump to ra, load a0 in the delay slot
   jr    $31
   ld    $4, (8 * 4)($4)

cc @yingopq @wzssyqa @MaskRay

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It is for the PS1, yes. I haven't tried that patch, however looking over it it doesn't seem to edit the libunwind function in UnwindRegistersRestore.S. Is the assembly in this file handled via code generation? Or is the code gen mentioned in that patch unrelated to libunwind?