Allow output constraints on "asm goto"

Summary:
Remove the restrictions that preventing "asm goto" from returning non-void
values. The values returned by "asm goto" are only valid on the "fallthrough"
path.

Reviewers: jyknight, nickdesaulniers, hfinkel

Reviewed By: jyknight, nickdesaulniers

Subscribers: rsmith, hiraditya, llvm-commits, cfe-commits, craig.topper, rnk

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D69876

1 files changed, 9 insertions, 0 deletions

diff --git a/llvm/include/llvm/CodeGen/MachineBasicBlock.h b/llvm/include/llvm/CodeGen/MachineBasicBlock.h
index ccdde78a0b2..cbcd0b61ecb 100644
--- a/llvm/include/llvm/CodeGen/MachineBasicBlock.h
+++ b/llvm/include/llvm/CodeGen/MachineBasicBlock.h
@@ -129,6 +129,9 @@ private:
   /// Indicate that this basic block is the entry block of a cleanup funclet.
   bool IsCleanupFuncletEntry = false;
 
+  /// Indicate that this basic block is the indirect dest of an INLINEASM_BR.
+  bool IsInlineAsmBrIndirectPad = false;
+
   /// since getSymbol is a relatively heavy-weight operation, the symbol
   /// is only computed once and is cached.
   mutable MCSymbol *CachedMCSymbol = nullptr;
@@ -408,6 +411,12 @@ public:
   /// Indicates if this is the entry block of a cleanup funclet.
   void setIsCleanupFuncletEntry(bool V = true) { IsCleanupFuncletEntry = V; }
 
+  /// Returns true if this is the indirect dest of an INLINEASM_BR.
+  bool isInlineAsmBrIndirectPad() const { return IsInlineAsmBrIndirectPad; }
+
+  /// Indicates if this is the indirect dest of an INLINEASM_BR.
+  void setIsInlineAsmBrIndirectPad(bool V = true) { IsInlineAsmBrIndirectPad = V; }
+
   /// Returns true if it is legal to hoist instructions into this block.
   bool isLegalToHoistInto() const;