[AMDGPU][NFC] Skip processing intrinsics that do not become real instructions

Reviewers: rampitec

Reviewed By: rampitec

Subscribers: arsenm, kzhuravl, jvesely, wdng, nhaehnle, yaxunl, dstuttard, tpr, t-tye, hiraditya, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D81260

Author: dfukalov

llvm/lib/Target/AMDGPU/AMDGPULibCalls.cpp

@@ -1730,7 +1730,9 @@ bool AMDGPUSimplifyLibCalls::runOnFunction(Function &F) {
       // Ignore non-calls.
       CallInst *CI = dyn_cast<CallInst>(I);
       ++I;
-      if (!CI) continue;
+      // Ignore intrinsics that do not become real instructions.
+      if (!CI || isa<DbgInfoIntrinsic>(CI) || CI->isLifetimeStartOrEnd())
+        continue;
 
       // Ignore indirect calls.
       Function *Callee = CI->getCalledFunction();

llvm/test/CodeGen/AMDGPU/simplify-libcalls2.ll

@@ -0,0 +1,24 @@
+; REQUIRES: asserts
+; RUN: opt -S -amdgpu-simplifylib -debug-only=amdgpu-simplifylib -mtriple=amdgcn-unknown-amdhsa -disable-output < %s 2>&1 | FileCheck %s
+
+; CHECK-NOT: AMDIC: try folding   call void @llvm.lifetime.start.p0i8
+; CHECK-NOT: AMDIC: try folding   call void @llvm.lifetime.end.p0i8
+; CHECK-NOT: AMDIC: try folding   call void @llvm.dbg.value
+
+define void @foo(i32 %i) {
+  call void @llvm.lifetime.start.p0i8(i64 1, i8* undef)
+  call void @llvm.lifetime.end.p0i8(i64 1, i8* undef)
+  call void @llvm.dbg.value(metadata i32 undef, metadata !DILocalVariable(name: "1", scope: !2), metadata !DIExpression()), !dbg !3
+  ret void
+}
+
+declare void @llvm.lifetime.start.p0i8(i64 immarg, i8* nocapture)
+declare void @llvm.lifetime.end.p0i8(i64 immarg, i8* nocapture)
+declare void @llvm.dbg.value(metadata, metadata, metadata)
+
+!llvm.module.flags = !{!1}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C, file: !DIFile(filename: "1", directory: "1"))
+!1 = !{i32 2, !"Debug Info Version", i32 3}
+!2 = distinct !DISubprogram(unit: !0)
+!3 = !DILocation(line: 1, column: 1, scope: !2)