Ensure conj_physical always does a physical conjugation

amjames · amjames · commit e1fe699c89f6 · 2025-03-14T22:41:11.000Z
When the argument tensor has a conj bit set. The conj_physical implementation will do `arg.conj().clone()`. Which is not a physical conjugation but a reversal of the conjugate view state. Instead we should unconditionally perform the conjugation of the underling data data, and ensure the argument conjugate bit is propagated to the result. ghstack-source-id: 2408bd2 Pull Request resolved: #149226
diff --git a/aten/src/ATen/native/UnaryOps.cpp b/aten/src/ATen/native/UnaryOps.cpp
@@ -617,10 +617,8 @@ Tensor& conj_physical_out(const Tensor& self, Tensor& result) {
 }
 
 Tensor _conj_physical(const Tensor& self) {
-  if (self.is_conj()) {
-    return self.conj().clone();
-  }
   auto result = at::empty_like(self);
+  result._set_conj(self.is_conj());
   return at::conj_physical_out(result, self);
 }
 

Original file line number	Diff line number	Diff line change
`@@ -617,10 +617,8 @@ Tensor& conj_physical_out(const Tensor& self, Tensor& result) {`
`617`	`617`	`}`
`618`	`618`
`619`	`619`	`Tensor _conj_physical(const Tensor& self) {`
`620`		`- if (self.is_conj()) {`
`621`		`- return self.conj().clone();`
`622`		`- }`
`623`	`620`	`auto result = at::empty_like(self);`
	`621`	`+ result._set_conj(self.is_conj());`
`624`	`622`	`return at::conj_physical_out(result, self);`
`625`	`623`	`}`
`626`	`624`