[llvm] [Transforms] Let amdgcn take advantage of sin(-x) --> -sin(x) (PR #79700)

[via llvm-commits]

https://github.com/AtariDreams created https://github.com/llvm/llvm-project/pull/79700

We do it for amdgcn_cos, and we should do it for amdgcn_sin as well.

>From a588b27f5e4358201016ac231d64ecc82496e80c Mon Sep 17 00:00:00 2001
From: Rose <83477269+AtariDreams at users.noreply.github.com>
Date: Sat, 27 Jan 2024 12:54:09 -0500
Subject: [PATCH] [Transforms] Let amdgcn take advantage of sin(-x) --> -sin(x)

We do it for amdgcn_cos, and we should do it for amdgcn_sin as well
---
 llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
index a647be2d26c7613..ce54d49323dc6eb 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
@@ -2497,11 +2497,12 @@ Instruction *InstCombinerImpl::visitCallInst(CallInst &CI) {
     }
     break;
   }
-  case Intrinsic::sin: {
+  case Intrinsic::sin:
+  case Intrinsic::amdgcn_sin: {
     Value *X;
     if (match(II->getArgOperand(0), m_OneUse(m_FNeg(m_Value(X))))) {
       // sin(-x) --> -sin(x)
-      Value *NewSin = Builder.CreateUnaryIntrinsic(Intrinsic::sin, X, II);
+      Value *NewSin = Builder.CreateUnaryIntrinsic(IID, X, II);
       Instruction *FNeg = UnaryOperator::CreateFNeg(NewSin);
       FNeg->copyFastMathFlags(II);
       return FNeg;