Change jal to call in zkVM entrypoint (risc0#1257)

As described in risc0#1243, our use of the `jal` instruction in our entrypoint breaks when the jump distance becomes too far. This PR changes the instruction to the `call` psuedo-instruction to allow the assembler flexibility to solve this issue and implement a far jump. Co-authored-by: @weikengchen Resolves: risc0#1243 --------- Co-authored-by: Frank Laub <[email protected]> Co-authored-by: Frank Laub <[email protected]>
nkysg · Dec 20, 2023 · b4b6ddf · b4b6ddf
1 parent 2a6026f
commit b4b6ddf
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Showing 3 changed files with 5 additions and 5 deletions.
diff --git a/risc0/build/src/docker.rs b/risc0/build/src/docker.rs
@@ -233,15 +233,15 @@ mod test {
         build("../../risc0/zkvm/methods/guest/Cargo.toml");
         compare_image_id(
             "risc0_zkvm_methods_guest/multi_test",
-            "f95f1a062cc386bcebe950e093c05b2064d0938d63c5522e7762618200204b29",
+            "1179a5fefa42c0ffd9c9defacb007f0e5c3b91b008726f1c334333e62998b1fd",
         );
         compare_image_id(
             "risc0_zkvm_methods_guest/hello_commit",
-            "d79504add318b06cb7150c0434b7fafaffe8c93c001271bb3c3d956b7b6a476f",
+            "4fe8d43b0b9f78d17b011adeba1cb2242cd3ce758772fbe9e43429e4d91d4f10",
         );
         compare_image_id(
             "risc0_zkvm_methods_guest/slice_io",
-            "0cdb7e93db5ce17d5646c7330fa3ffc86ef4433733a2965422a232e4ee330547",
+            "fcc440cb194deb4741cc6c919acad75cf95c8b548191b90ebd748fe644bd26fc",
         );
     }
 }
diff --git a/risc0/zkvm/platform/src/rust_rt.rs b/risc0/zkvm/platform/src/rust_rt.rs
@@ -74,7 +74,7 @@ mod entrypoint {
         .option pop
         la sp, {0}
         lw sp, 0(sp)
-        jal ra, __start;
+        call __start;
     "#,
         sym STACK_TOP
     );

diff --git a/risc0/zkvm/src/guest/mod.rs b/risc0/zkvm/src/guest/mod.rs
@@ -163,7 +163,7 @@ _start:
     .option pop;
     la sp, {0}
     lw sp, 0(sp)
-    jal ra, __start;
+    call __start;
 "#,
     sym STACK_TOP
 );