[PATCH] D125730: [WebAssembly] Strip TLS when "atomics" is not enabled

[Dan Gohman via Phabricator via llvm-commits]

sunfish created this revision.
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With f3b4f99007cdcb3306484c9a39d31addc20aaa69, the exclusive source of truth for whether threads are supported is the -matomics flag. Accordingly, strip TLS flags when -matomic is not specified, even if bulk-memory is specified and it would theoretically be supportable. This allows the backend to compile TLS variables when -mbulk-memory is enabled but threads are not enabled.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D125730

Files:
  llvm/lib/Target/WebAssembly/WebAssemblyTargetMachine.cpp
  llvm/test/CodeGen/WebAssembly/target-features-tls.ll
  llvm/test/CodeGen/WebAssembly/tls-general-dynamic.ll
  llvm/test/CodeGen/WebAssembly/tls-local-exec.ll


Index: llvm/test/CodeGen/WebAssembly/tls-local-exec.ll
===================================================================
--- llvm/test/CodeGen/WebAssembly/tls-local-exec.ll
+++ llvm/test/CodeGen/WebAssembly/tls-local-exec.ll
@@ -1,6 +1,6 @@
-; RUN: llc < %s -asm-verbose=false -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -mattr=+bulk-memory | FileCheck %s --check-prefixes=CHECK,TLS
-; RUN: llc < %s -asm-verbose=false -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -mattr=+bulk-memory -fast-isel | FileCheck %s --check-prefixes=CHECK,TLS
-; RUN: llc < %s -asm-verbose=false -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -mattr=-bulk-memory | FileCheck %s --check-prefixes=CHECK,NO-TLS
+; RUN: llc < %s -asm-verbose=false -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -mcpu=mvp -mattr=+bulk-memory,+atomics | FileCheck %s --check-prefixes=CHECK,TLS
+; RUN: llc < %s -asm-verbose=false -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -mcpu=mvp -mattr=+bulk-memory,+atomics -fast-isel | FileCheck %s --check-prefixes=CHECK,TLS
+; RUN: llc < %s -asm-verbose=false -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -mcpu=mvp -mattr=-bulk-memory,+atomics | FileCheck %s --check-prefixes=CHECK,NO-TLS
 target triple = "wasm32-unknown-unknown"
 
 ; CHECK-LABEL: address_of_tls:
Index: llvm/test/CodeGen/WebAssembly/tls-general-dynamic.ll
===================================================================
--- llvm/test/CodeGen/WebAssembly/tls-general-dynamic.ll
+++ llvm/test/CodeGen/WebAssembly/tls-general-dynamic.ll
@@ -1,8 +1,8 @@
-; RUN: not --crash llc < %s -asm-verbose=false -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -mattr=+bulk-memory 2>&1 | FileCheck %s --check-prefix=ERROR
-; RUN: not --crash llc < %s -asm-verbose=false -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -mattr=+bulk-memory -fast-isel 2>&1 | FileCheck %s --check-prefix=ERROR
-; RUN: llc < %s -asm-verbose=false -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -mattr=+bulk-memory --mtriple wasm32-unknown-emscripten | FileCheck %s --check-prefixes=CHECK,TLS
-; RUN: llc < %s -asm-verbose=false -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -mattr=+bulk-memory --mtriple wasm32-unknown-emscripten -fast-isel | FileCheck %s --check-prefixes=CHECK,TLS
-; RUN: llc < %s -asm-verbose=false -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -mattr=-bulk-memory | FileCheck %s --check-prefixes=CHECK,NO-TLS
+; RUN: not --crash llc < %s -asm-verbose=false -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -mcpu=mvp -mattr=+bulk-memory,+atomics 2>&1 | FileCheck %s --check-prefix=ERROR
+; RUN: not --crash llc < %s -asm-verbose=false -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -mcpu=mvp -mattr=+bulk-memory,+atomics -fast-isel 2>&1 | FileCheck %s --check-prefix=ERROR
+; RUN: llc < %s -asm-verbose=false -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -mcpu=mvp -mattr=+bulk-memory,+atomics --mtriple wasm32-unknown-emscripten | FileCheck %s --check-prefixes=CHECK,TLS
+; RUN: llc < %s -asm-verbose=false -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -mcpu=mvp -mattr=+bulk-memory,+atomics --mtriple wasm32-unknown-emscripten -fast-isel | FileCheck %s --check-prefixes=CHECK,TLS
+; RUN: llc < %s -asm-verbose=false -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -mcpu=mvp -mattr=-bulk-memory,+atomics | FileCheck %s --check-prefixes=CHECK,NO-TLS
 target triple = "wasm32-unknown-unknown"
 
 ; ERROR: LLVM ERROR: only -ftls-model=local-exec is supported for now on non-Emscripten OSes: variable tls
Index: llvm/test/CodeGen/WebAssembly/target-features-tls.ll
===================================================================
--- llvm/test/CodeGen/WebAssembly/target-features-tls.ll
+++ llvm/test/CodeGen/WebAssembly/target-features-tls.ll
@@ -1,5 +1,5 @@
-; RUN: llc < %s -mattr=-bulk-memory | FileCheck %s --check-prefixes NO-BULK-MEM
-; RUN: llc < %s -mattr=+bulk-memory | FileCheck %s --check-prefixes BULK-MEM
+; RUN: llc < %s -mcpu=mvp -mattr=-bulk-memory,+atomics | FileCheck %s --check-prefixes NO-BULK-MEM
+; RUN: llc < %s -mcpu=mvp -mattr=+bulk-memory,+atomics | FileCheck %s --check-prefixes BULK-MEM
 
 ; Test that the target features section contains -atomics or +atomics
 ; for modules that have thread local storage in their source.
@@ -10,7 +10,10 @@
 
 ; -bulk-memory
 ; NO-BULK-MEM-LABEL: .custom_section.target_features,"",@
-; NO-BULK-MEM-NEXT: .int8 1
+; NO-BULK-MEM-NEXT: .int8 2
+; NO-BULK-MEM-NEXT: .int8 43
+; NO-BULK-MEM-NEXT: .int8 7
+; NO-BULK-MEM-NEXT: .ascii "atomics"
 ; NO-BULK-MEM-NEXT: .int8 45
 ; NO-BULK-MEM-NEXT: .int8 10
 ; NO-BULK-MEM-NEXT: .ascii "shared-mem"
@@ -18,7 +21,10 @@
 
 ; +bulk-memory
 ; BULK-MEM-LABEL: .custom_section.target_features,"",@
-; BULK-MEM-NEXT: .int8 1
+; BULK-MEM-NEXT: .int8 2
+; BULK-MEM-NEXT: .int8 43
+; BULK-MEM-NEXT: .int8 7
+; BULK-MEM-NEXT: .ascii "atomics"
 ; BULK-MEM-NEXT: .int8 43
 ; BULK-MEM-NEXT: .int8 11
 ; BULK-MEM-NEXT: .ascii "bulk-memory"
Index: llvm/lib/Target/WebAssembly/WebAssemblyTargetMachine.cpp
===================================================================
--- llvm/lib/Target/WebAssembly/WebAssemblyTargetMachine.cpp
+++ llvm/lib/Target/WebAssembly/WebAssemblyTargetMachine.cpp
@@ -203,11 +203,13 @@
     bool StrippedAtomics = false;
     bool StrippedTLS = false;
 
-    if (!Features[WebAssembly::FeatureAtomics])
+    if (!Features[WebAssembly::FeatureAtomics]) {
       StrippedAtomics = stripAtomics(M);
+      StrippedTLS = stripThreadLocals(M);
+    }
 
     if (!Features[WebAssembly::FeatureBulkMemory])
-      StrippedTLS = stripThreadLocals(M);
+      StrippedTLS |= stripThreadLocals(M);
 
     if (StrippedAtomics && !StrippedTLS)
       stripThreadLocals(M);


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