[PATCH] D53765: [RFC prototype] Implementation of asm-goto support in LLVM

Mon Jan 14 13:05:37 PST 2019

craig.topper marked an inline comment as done.
craig.topper added inline comments.

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Comment at: lib/CodeGen/AsmPrinter/AsmPrinter.cpp:3006-3007
+  if (AGI != Pred->end()) {
+    // FIXME: this is crude, but the asm-goto sometimes seems to be the second-
+    // to-last instruction. Find a prettier way to check this.
+    const auto &AG = *AGI;
----------------
void wrote:
> This comment and the FIXME above it have me confused. Isn't the point of `callbr` to convert *all* asm goto statements into `callbr`? If so, then they should automatically be at the end of the basic block. What are the situations where it won't follow this?
This is MachineIR not IR. INLINEASM has its own MachineInstr opcode which is not a terminator. Currently asm-goto is still using that.

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https://reviews.llvm.org/D53765