[llvm] [AMDGPU] Add AMDGPU-specific module splitting (PR #89245)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,54 @@
+; RUN: llvm-split -o %t %s -j 3 -mtriple amdgcn-amd-amdhsa
+; RUN: llvm-dis -o - %t0 | FileCheck --check-prefix=CHECK0 %s
+; RUN: llvm-dis -o - %t1 | FileCheck --check-prefix=CHECK1 %s
+; RUN: llvm-dis -o - %t2 | FileCheck --check-prefix=CHECK2 %s
+
+; 3 kernels with each their own dependencies should go into 3
+; distinct partitions. The most expensive kernel should be
+; seen first and go into the last partition.
+
+; CHECK0-NOT: define
+; CHECK0: define amdgpu_kernel void @C
+; CHECK0: define internal void @HelperC
+; CHECK0-NOT: define
+
+; CHECK1-NOT: define
+; CHECK1: define amdgpu_kernel void @A
+; CHECK1: define internal void @HelperA
+; CHECK1-NOT: define
+
+; CHECK2-NOT: define
+; CHECK2: define amdgpu_kernel void @B
+; CHECK2: define internal void @HelperB
+; CHECK2-NOT: define
+
+
+define amdgpu_kernel void @A() {
+    call void @HelperA()
+    ret void
+}
+
+define internal void @HelperA() {
+    ret void
+}
+
+define amdgpu_kernel void @B() {
+    store i64 42, ptr undef
+    store i64 43, ptr undef
+    store i64 44, ptr undef
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arsenm wrote:

Avoid UB in tests, and avoid undef 

https://github.com/llvm/llvm-project/pull/89245