[clang] [llvm] [Matrix] Implement matrix support for the `pow` intrinsic (PR #212514)

[Kaitlin Peng via cfe-commits]

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@@ -1,5 +1,5 @@
 // RUN: %clang_cc1 -finclude-default-header -triple dxilv1.0-unknown-shadermodel6.0-library -std=hlsl202x -emit-llvm-only -disable-llvm-passes -DFUNC=atan2 %s 2>&1 | FileCheck %s -DFUNC=atan2 --check-prefixes=CHECK,CHECK-MAT
-// RUN: %clang_cc1 -finclude-default-header -triple dxilv1.0-unknown-shadermodel6.0-library -std=hlsl202x -emit-llvm-only -disable-llvm-passes -DFUNC=pow %s 2>&1 | FileCheck %s -DFUNC=pow
+// RUN: %clang_cc1 -finclude-default-header -triple dxilv1.0-unknown-shadermodel6.0-library -std=hlsl202x -emit-llvm-only -disable-llvm-passes -DFUNC=pow %s 2>&1 | FileCheck %s -DFUNC=pow --check-prefixes=CHECK,CHECK-MAT
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kmpeng wrote:

I wasn't planning on adding compat overloads to matrix `pow` given our discussions, but without them, the matrix test in this file fails because of the changes made by `atan2`. For it to not fail, we either have to keep the `pow` compat overloads (will need compat overloads for `step` in the future too), split `atan2` out of this file, or remove the `atan2` overloads. Didn't know what approach was correct.

https://github.com/llvm/llvm-project/pull/212514