[AArch64] Assert expandMOVImm prioritizes optimal single MOVZ/N
#169341
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expandMOVImm prioritizes optimal single MOVZ/…expandMOVImm prioritizes optimal single MOVZ/N
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✅ With the latest revision this PR passed the C/C++ code formatter. |
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@llvm/pr-subscribers-backend-aarch64 Author: Tomer Shafir (tomershafir) ChangesThe expansion of move immediate in Full diff: https://github.com/llvm/llvm-project/pull/169341.diff 1 Files Affected:
diff --git a/llvm/lib/Target/AArch64/AArch64ExpandImm.cpp b/llvm/lib/Target/AArch64/AArch64ExpandImm.cpp
index e9660ac140301..ae5818419cba5 100644
--- a/llvm/lib/Target/AArch64/AArch64ExpandImm.cpp
+++ b/llvm/lib/Target/AArch64/AArch64ExpandImm.cpp
@@ -549,6 +549,8 @@ void AArch64_IMM::expandMOVImm(uint64_t Imm, unsigned BitSize,
// Prefer MOVZ/MOVN over ORR because of the rules for the "mov" alias.
if ((BitSize / 16) - OneChunks <= 1 || (BitSize / 16) - ZeroChunks <= 1) {
expandMOVImmSimple(Imm, BitSize, OneChunks, ZeroChunks, Insn);
+ assert(Insn.size() == 1 &&
+ "Move of immediate should have expanded to a single MOVZ/MOVN");
return;
}
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The expansion of move immediate in `expandMOVImm` follows the priority of the `MOV` alias. In addition, the selection there properly prefers expansion based on perf optimality order. This change adds a simple assert that `expandMOVImmSimple` expands a single optimal MOVZ/N.
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…vm#169341) The expansion of move immediate in `expandMOVImm` follows the priority of the `MOV` alias. In addition, the selection there properly prefers expansion based on perf optimality order. This change adds a simple assert that `expandMOVImmSimple` expands a single optimal MOVZ/MOVK.
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The expansion of move immediate in
expandMOVImmfollows the priority of theMOValias. In addition, the selection there properly prefers expansion based on perf optimality order. This change adds a simple assert thatexpandMOVImmSimpleexpands a single optimal MOVZ/MOVK.