[llvm] 2dade00 - [Analysis] Attribute Range should not prevent tail call optimization (#91122)

[via llvm-commits]

Author: Jinsong Ji
Date: 2024-05-07T22:02:10-04:00
New Revision: 2dade0041a62b192e9bde24ae6bbe6208f027523

URL: https://github.com/llvm/llvm-project/commit/2dade0041a62b192e9bde24ae6bbe6208f027523
DIFF: https://github.com/llvm/llvm-project/commit/2dade0041a62b192e9bde24ae6bbe6208f027523.diff

LOG: [Analysis] Attribute Range should not prevent tail call optimization (#91122)

- Remove Range attr when comparing for tailcall
- Add test for testcall with range

Added: 
    llvm/test/CodeGen/X86/tailcall-range.ll

Modified: 
    llvm/lib/CodeGen/Analysis.cpp
    llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/CodeGen/Analysis.cpp b/llvm/lib/CodeGen/Analysis.cpp
index af7643d93591f..e693cdbd0ccc1 100644
--- a/llvm/lib/CodeGen/Analysis.cpp
+++ b/llvm/lib/CodeGen/Analysis.cpp
@@ -593,9 +593,10 @@ bool llvm::attributesPermitTailCall(const Function *F, const Instruction *I,
 
   // Following attributes are completely benign as far as calling convention
   // goes, they shouldn't affect whether the call is a tail call.
-  for (const auto &Attr : {Attribute::Alignment, Attribute::Dereferenceable,
-                           Attribute::DereferenceableOrNull, Attribute::NoAlias,
-                           Attribute::NonNull, Attribute::NoUndef}) {
+  for (const auto &Attr :
+       {Attribute::Alignment, Attribute::Dereferenceable,
+        Attribute::DereferenceableOrNull, Attribute::NoAlias,
+        Attribute::NonNull, Attribute::NoUndef, Attribute::Range}) {
     CallerAttrs.removeAttribute(Attr);
     CalleeAttrs.removeAttribute(Attr);
   }

diff  --git a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
index 336d89fbcf638..9ec3ac4f99915 100644
--- a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
@@ -62,9 +62,10 @@ bool TargetLowering::isInTailCallPosition(SelectionDAG &DAG, SDNode *Node,
   // the return. Ignore following attributes because they don't affect the
   // call sequence.
   AttrBuilder CallerAttrs(F.getContext(), F.getAttributes().getRetAttrs());
-  for (const auto &Attr : {Attribute::Alignment, Attribute::Dereferenceable,
-                           Attribute::DereferenceableOrNull, Attribute::NoAlias,
-                           Attribute::NonNull, Attribute::NoUndef})
+  for (const auto &Attr :
+       {Attribute::Alignment, Attribute::Dereferenceable,
+        Attribute::DereferenceableOrNull, Attribute::NoAlias,
+        Attribute::NonNull, Attribute::NoUndef, Attribute::Range})
     CallerAttrs.removeAttribute(Attr);
 
   if (CallerAttrs.hasAttributes())

diff  --git a/llvm/test/CodeGen/X86/tailcall-range.ll b/llvm/test/CodeGen/X86/tailcall-range.ll
new file mode 100644
index 0000000000000..6ae7405ebc4a9
--- /dev/null
+++ b/llvm/test/CodeGen/X86/tailcall-range.ll
@@ -0,0 +1,53 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 4
+; RUN: llc -mtriple=x86_64-linux < %s | FileCheck %s
+
+define range(i32 0, 2) i32 @foo(ptr %this) {
+; CHECK-LABEL: foo:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    movzbl (%rdi), %eax
+; CHECK-NEXT:    retq
+entry:
+  %call = load volatile i1, ptr %this, align 1
+  %spec.select = zext i1 %call to i32
+  ret i32 %spec.select
+}
+
+define range(i32 0, 2) i32 @bar(ptr %this) {
+; CHECK-LABEL: bar:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    xorl %edi, %edi
+; CHECK-NEXT:    jmp foo at PLT # TAILCALL
+entry:
+  %ret = musttail call i32 @foo(ptr null)
+  ret i32 %ret
+}
+
+declare i64 @llvm.llround.f32(float) nounwind readnone
+define range(i64 0, 8) i64 @testmsxs(float %x) {
+; CHECK-LABEL: testmsxs:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    jmp llroundf at PLT # TAILCALL
+entry:
+  %ret = tail call i64 @llvm.llround.f32(float %x)
+  ret i64 %ret
+}
+
+declare i32 @callee()
+
+define range(i32 0, 2) i32 @func_with_range_attr() {
+; CHECK-LABEL: func_with_range_attr:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    jmp callee at PLT # TAILCALL
+entry:
+  %ret = musttail call i32 @callee()
+  ret i32 %ret
+}
+
+define i32 @call_with_range_attr() {
+; CHECK-LABEL: call_with_range_attr:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    jmp callee at PLT # TAILCALL
+entry:
+  %ret = musttail call range(i32 0, 2) i32 @callee()
+  ret i32 %ret
+}