81 lines
		
	
	
		
			1.8 KiB
		
	
	
	
		
			LLVM
		
	
	
	
			
		
		
	
	
			81 lines
		
	
	
		
			1.8 KiB
		
	
	
	
		
			LLVM
		
	
	
	
| ; RUN: opt -globalopt -S < %s | FileCheck %s
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| 
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| @G1 = internal global i32 5
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| @G2 = internal global i32 5
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| @G3 = internal global i32 5
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| @G4 = internal global i32 5
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| @G5 = internal global i32 5
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| 
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| ; CHECK-LABEL: @test1
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| define internal i32 @test1() norecurse {
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| ; CHECK-NOT: @G1
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|   store i32 4, i32* @G1
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|   %a = load i32, i32* @G1
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| ; CHECK: ret
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|   ret i32 %a
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| }
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| 
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| ; The load comes before the store which makes @G2 live before the call.
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| ; CHECK-LABEL: @test2
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| define internal i32 @test2() norecurse {
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| ; CHECK-NOT: %G2
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|   %a = load i32, i32* @G2
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|   store i32 4, i32* @G2
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| ; CHECK: ret
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|   ret i32 %a
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| }
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| 
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| ; This global is indexed by a GEP - this makes it partial alias and we bail out.
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| ; FIXME: We don't actually have to bail out in this case.
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| 
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| ; CHECK-LABEL: @test3
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| define internal i32 @test3() norecurse {
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| ; CHECK-NOT: %G3
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|   %x = getelementptr i32,i32* @G3, i32 0
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|   %a = load i32, i32* %x
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|   store i32 4, i32* @G3
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| ; CHECK: ret
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|   ret i32 %a
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| }
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| 
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| ; The global is casted away to a larger type then loaded. The store only partially
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| ; covers the load, so we must not demote.
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| 
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| ; CHECK-LABEL: @test4
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| define internal i32 @test4() norecurse {
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| ; CHECK-NOT: %G4
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|   store i32 4, i32* @G4
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|   %x = bitcast i32* @G4 to i64*
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|   %a = load i64, i64* %x
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|   %b = trunc i64 %a to i32
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| ; CHECK: ret
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|   ret i32 %b
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| }
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| 
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| ; The global is casted away to a smaller type then loaded. This one is fine.
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| 
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| ; CHECK-LABEL: @test5
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| define internal i32 @test5() norecurse {
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| ; CHECK-NOT: @G5
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|   store i32 4, i32* @G5
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|   %x = bitcast i32* @G5 to i16*
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|   %a = load i16, i16* %x
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|   %b = zext i16 %a to i32
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| ; CHECK: ret
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|   ret i32 %b
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| }
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| 
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| define i32 @main() norecurse {
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|   %a = call i32 @test1()
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|   %b = call i32 @test2()
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|   %c = call i32 @test3()
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|   %d = call i32 @test4()
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|   %e = call i32 @test5()
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| 
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|   %x = or i32 %a, %b
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|   %y = or i32 %x, %c
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|   %z = or i32 %y, %d
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|   %w = or i32 %z, %e
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|   ret i32 %w
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| }
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