builder: fix atomic_cmpxchg for SPIR-V OpAtomicCompareExchange.

eddyb · LegNeato · commit bb0e60514449 · 2024-09-21T08:20:05.000-04:00
diff --git a/crates/rustc_codegen_spirv/src/builder/builder_methods.rs b/crates/rustc_codegen_spirv/src/builder/builder_methods.rs
@@ -2310,10 +2310,9 @@ impl<'a, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'tcx> {
             )
             .unwrap()
             .with_type(access_ty);
-        let result = self.bitcast(result, ty);
 
-        let val = self.extract_value(result, 0);
-        let success = self.extract_value(result, 1);
+        let val = self.bitcast(result, ty);
+        let success = self.icmp(IntPredicate::IntEQ, val, cmp);
 
         (val, success)
     }

Original file line number	Diff line number	Diff line change
`@@ -2310,10 +2310,9 @@ impl<'a, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'tcx> {`
`2310`	`2310`	`)`
`2311`	`2311`	`.unwrap()`
`2312`	`2312`	`.with_type(access_ty);`
`2313`		`- let result = self.bitcast(result, ty);`
`2314`	`2313`
`2315`		`- let val = self.extract_value(result, 0);`
`2316`		`- let success = self.extract_value(result, 1);`
	`2314`	`+ let val = self.bitcast(result, ty);`
	`2315`	`+ let success = self.icmp(IntPredicate::IntEQ, val, cmp);`
`2317`	`2316`
`2318`	`2317`	`(val, success)`
`2319`	`2318`	`}`