37 lines
		
	
	
		
			1.1 KiB
		
	
	
	
		
			LLVM
		
	
	
	
			
		
		
	
	
			37 lines
		
	
	
		
			1.1 KiB
		
	
	
	
		
			LLVM
		
	
	
	
| ; RUN: llc -mtriple=thumbv7-linux-gnueabi -o - %s | FileCheck %s
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| 
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| ; This alloca is just large enough that FrameLowering decides it needs a frame
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| ; to guarantee access, based on the range of ldrex.
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| 
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| ; The actual alloca size is a bit of black magic, unfortunately: the real
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| ; maximum accessible is 1020, but FrameLowering adds 16 bytes to its estimated
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| ; stack size just because so the alloca is not actually the what the limit gets
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| ; compared to. The important point is that we don't go up to ~4096, which is the
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| ; default with no strange instructions.
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| define void @test_large_frame() {
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| ; CHECK-LABEL: test_large_frame:
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| ; CHECK: push
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| ; CHECK: sub.w sp, sp, #1004
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| 
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|   %ptr = alloca i32, i32 251
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| 
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|   %addr = getelementptr i32, i32* %ptr, i32 1
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|   call i32 @llvm.arm.ldrex.p0i32(i32* %addr)
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|   ret void
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| }
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| 
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| ; This alloca is just is just the other side of the limit, so no frame
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| define void @test_small_frame() {
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| ; CHECK-LABEL: test_small_frame:
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| ; CHECK-NOT: push
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| ; CHECK: sub.w sp, sp, #1000
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| 
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|   %ptr = alloca i32, i32 250
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| 
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|   %addr = getelementptr i32, i32* %ptr, i32 1
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|   call i32 @llvm.arm.ldrex.p0i32(i32* %addr)
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|   ret void
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| }
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| 
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| declare i32 @llvm.arm.ldrex.p0i32(i32*)
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