[llvm] Add support for atomic instruction on floating-point numbers (PR #81683)

[Michal Paszkowski via llvm-commits]

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@@ -0,0 +1,43 @@
+; RUN: not llc -O0 -mtriple=spirv32-unknown-unknown %s -o %t.spvt 2>&1 | FileCheck %s --check-prefix=CHECK-ERROR
+
+; RUN: llc -O0 -mtriple=spirv32-unknown-unknown --spirv-extensions=SPV_EXT_shader_atomic_float_add %s -o - | FileCheck %s
+
+; CHECK-ERROR: LLVM ERROR: The atomic float instruction requires the following SPIR-V extension: SPV_EXT_shader_atomic_float_add
+
+; CHECK: Capability AtomicFloat64AddEXT
+; CHECK: Extension "SPV_EXT_shader_atomic_float_add"
+; CHECK-DAG: %[[TyFP64:[0-9]+]] = OpTypeFloat 64
+; CHECK-DAG: %[[TyInt32:[0-9]+]] = OpTypeInt 32 0
+; CHECK-DAG: %[[Const0:[0-9]+]] = OpConstant %[[TyFP64]] 0
+; CHECK-DAG: %[[Const42:[0-9]+]] = OpConstant %[[TyFP64]] 42
+; CHECK-DAG: %[[ScopeDevice:[0-9]+]] = OpConstant %[[TyInt32]] 1
+; CHECK-DAG: %[[MemSeqCst:[0-9]+]] = OpConstant %[[TyInt32]] 16
+; CHECK-DAG: %[[TyFP64Ptr:[0-9]+]] = OpTypePointer {{[a-zA-Z]+}} %[[TyFP64]]
+; CHECK-DAG: %[[DblPtr:[0-9]+]] = OpVariable %[[TyFP64Ptr]] {{[a-zA-Z]+}} %[[Const0]]
+; CHECK: OpAtomicFAddEXT %[[TyFP64]] %[[DblPtr]] %[[ScopeDevice]] %[[MemSeqCst]] %[[Const42]]
+; CHECK: %[[Const42Neg:[0-9]+]] = OpFNegate %[[TyFP64]] %[[Const42]]
+; CHECK: OpAtomicFAddEXT %[[TyFP64]] %[[DblPtr]] %[[ScopeDevice]] %[[MemSeqCst]] %[[Const42Neg]]
+; CHECK: OpAtomicFAddEXT %[[TyFP64]] %[[DblPtr]] %[[ScopeDevice]] %[[MemSeqCst]] %[[Const42]]
+
+target datalayout = "e-i64:64-v16:16-v24:32-v32:32-v48:64-v96:128-v192:256-v256:256-v512:512-v1024:1024"
+target triple = "spir64"
+
+ at f = common dso_local local_unnamed_addr addrspace(1) global double 0.000000e+00, align 8
+
+define dso_local spir_func void @test1() local_unnamed_addr {
+entry:
+  %0 = atomicrmw fadd ptr addrspace(1) @f, double 42.000000e+00 seq_cst
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michalpaszkowski wrote:

Please name all virtual registers. While, I don't mind no names/just numbering, this has been brought up by other LLVM maintainers in periodic review of the SPIR-V backend codebase. One reason is to make editing tests easier.

https://github.com/llvm/llvm-project/pull/81683