[llvm] [X86] Truncate i64 add/sub/mul arithmetic to i32 with known zeros in upper 32 bits (PR #143313)

[Phoebe Wang via llvm-commits]

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@@ -0,0 +1,31 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc < %s -mtriple=i686-unknown-unknown | FileCheck %s --check-prefix=X86
+; RUN: llc < %s -mtriple=x86_64-linux -verify-machineinstrs | FileCheck %s --check-prefix=X64-LINUX
+; RUN: llc < %s -mtriple=x86_64-win32 | FileCheck %s --check-prefix=X64-WIN32
+
+define i64 @test1(i16 %x) nounwind {
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phoebewang wrote:

Isn't it already generated the same code? https://godbolt.org/z/9Tqxco1ve

https://github.com/llvm/llvm-project/pull/143313