// Conversion to BIC is free, and means we can use ~Imm instead.
return std::min(getIntImmCost(Imm, Ty), getIntImmCost(~Imm, Ty));
+ if (Opcode == Instruction::ICmp && Imm.isNegative() &&
+ Ty->getIntegerBitWidth() == 32) {
+ int64_t NegImm = -Imm.getSExtValue();
+ if (ST->isThumb2() && NegImm < 1<<12)
+ // icmp X, #-C -> cmn X, #C
+ return 0;
+ if (ST->isThumb() && NegImm < 1<<8)
+ // icmp X, #-C -> adds X, #C
+ return 0;
+ }
+
return getIntImmCost(Imm, Ty);
}
ret void
}
+; CHECK: Function: test_icmp_neg
+; CHECK-NOT: Collect constant
+define void @test_icmp_neg(i1 %cond, i32 %arg, i32 %arg2) {
+entry:
+ %a = icmp ne i32 %arg, -5
+ call void @g2(i1 %a)
+ br i1 %cond, label %true, label %ret
+
+true:
+ %b = icmp ne i32 %arg2, -5
+ call void @g2(i1 %b)
+ br label %ret
+
+ret:
+ ret void
+}
+declare void @g2(i1)
+
+; CHECK: Function: test_icmp_neg2
+; CHECK: Hoist constant (i32 -500) to BB entry
+define void @test_icmp_neg2(i1 %cond, i32 %arg, i32 %arg2) {
+entry:
+ %a = icmp ne i32 %arg, -500
+ call void @g2(i1 %a)
+ br i1 %cond, label %true, label %ret
+
+true:
+ %b = icmp ne i32 %arg2, -500
+ call void @g2(i1 %b)
+ br label %ret
+
+ret:
+ ret void
+}