[bug] Fixed a bug in Vec::half() that halved to ZMM instead of XMM

kobalicek · kobalicek · commit 9888fcf2133f · 2025-11-13T21:50:54.000+01:00
diff --git a/asmjit/x86/x86operand.cpp b/asmjit/x86/x86operand.cpp
@@ -141,6 +141,10 @@ UNIT(x86_operand) {
   EXPECT_EQ(zmm7.ymm(), ymm7);
   EXPECT_EQ(zmm7.zmm(), zmm7);
 
+  EXPECT_EQ(xmm4.half(), xmm4);
+  EXPECT_EQ(ymm4.half(), xmm4);
+  EXPECT_EQ(zmm4.half(), ymm4);
+
   INFO("Checking x86::Mm register properties");
   EXPECT_TRUE(Mm().is_reg());
   EXPECT_TRUE(mm2.is_reg());
diff --git a/asmjit/x86/x86operand.h b/asmjit/x86/x86operand.h
@@ -237,7 +237,7 @@ class Vec : public UniVec {
   //! was ZMM, or XMM for whatever else input.
   [[nodiscard]]
   ASMJIT_INLINE_CONSTEXPR Vec half() const noexcept {
-    return Vec(is_vec512() ? signature_of_t<RegType::kVec256>() : signature_of_t<RegType::kVec512>(), id());
+    return Vec(is_vec512() ? signature_of_t<RegType::kVec256>() : signature_of_t<RegType::kVec128>(), id());
   }
 
   //! \}

Original file line number	Diff line number	Diff line change
`@@ -237,7 +237,7 @@ class Vec : public UniVec {`
`237`	`237`	`//! was ZMM, or XMM for whatever else input.`
`238`	`238`	`[[nodiscard]]`
`239`	`239`	`ASMJIT_INLINE_CONSTEXPR Vec half() const noexcept {`
`240`		`- return Vec(is_vec512() ? signature_of_t<RegType::kVec256>() : signature_of_t<RegType::kVec512>(), id());`
	`240`	`+ return Vec(is_vec512() ? signature_of_t<RegType::kVec256>() : signature_of_t<RegType::kVec128>(), id());`
`241`	`241`	`}`
`242`	`242`
`243`	`243`	`//! \}`