96 lines
		
	
	
		
			3.2 KiB
		
	
	
	
		
			LLVM
		
	
	
	
			
		
		
	
	
			96 lines
		
	
	
		
			3.2 KiB
		
	
	
	
		
			LLVM
		
	
	
	
| ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
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| ; RUN: opt -S -instcombine < %s | FileCheck %s
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| 
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| define i16 @foo(i16 %x)  {
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| ; CHECK-LABEL: @foo(
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| ; CHECK-NEXT:    [[T1:%.*]] = and i16 [[X:%.*]], 255
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| ; CHECK-NEXT:    ret i16 [[T1]]
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| ;
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|   %t1 = and i16 %x, 255
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|   %t2 = zext i16 %t1 to i32
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|   %t3 = icmp ult i32 %t2, 255
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|   %t4 = select i1 %t3, i32 %t2, i32 255
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|   %t5 = trunc i32 %t4 to i16
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|   %t6 = and i16 %t5, 255
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|   ret i16 %t6
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| }
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| 
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| ; This contains a min/max pair to clamp a value to 12 bits.
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| ; By analyzing the clamp pattern, we can tell the add doesn't have signed overflow.
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| define i16 @min_max_clamp(i16 %x) {
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| ; CHECK-LABEL: @min_max_clamp(
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| ; CHECK-NEXT:    [[A:%.*]] = icmp sgt i16 [[X:%.*]], -2048
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| ; CHECK-NEXT:    [[B:%.*]] = select i1 [[A]], i16 [[X]], i16 -2048
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| ; CHECK-NEXT:    [[C:%.*]] = icmp slt i16 [[B]], 2047
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| ; CHECK-NEXT:    [[D:%.*]] = select i1 [[C]], i16 [[B]], i16 2047
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| ; CHECK-NEXT:    [[E:%.*]] = add nsw i16 [[D]], 1
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| ; CHECK-NEXT:    ret i16 [[E]]
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| ;
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|   %a = icmp sgt i16 %x, -2048
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|   %b = select i1 %a, i16 %x, i16 -2048
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|   %c = icmp slt i16 %b, 2047
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|   %d = select i1 %c, i16 %b, i16 2047
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|   %e = add i16 %d, 1
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|   ret i16 %e
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| }
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| 
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| ; Same as above with min/max reversed.
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| define i16 @min_max_clamp_2(i16 %x) {
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| ; CHECK-LABEL: @min_max_clamp_2(
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| ; CHECK-NEXT:    [[A:%.*]] = icmp slt i16 [[X:%.*]], 2047
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| ; CHECK-NEXT:    [[B:%.*]] = select i1 [[A]], i16 [[X]], i16 2047
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| ; CHECK-NEXT:    [[C:%.*]] = icmp sgt i16 [[B]], -2048
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| ; CHECK-NEXT:    [[D:%.*]] = select i1 [[C]], i16 [[B]], i16 -2048
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| ; CHECK-NEXT:    [[E:%.*]] = add nsw i16 [[D]], 1
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| ; CHECK-NEXT:    ret i16 [[E]]
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| ;
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|   %a = icmp slt i16 %x, 2047
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|   %b = select i1 %a, i16 %x, i16 2047
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|   %c = icmp sgt i16 %b, -2048
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|   %d = select i1 %c, i16 %b, i16 -2048
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|   %e = add i16 %d, 1
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|   ret i16 %e
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| }
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| 
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| ; This contains a min/max pair to clamp a value to 12 bits.
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| ; By analyzing the clamp pattern, we can tell that the second add doesn't
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| ; overflow the original type and can be moved before the extend.
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| define i32 @min_max_clamp_3(i16 %x) {
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| ; CHECK-LABEL: @min_max_clamp_3(
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| ; CHECK-NEXT:    [[A:%.*]] = icmp sgt i16 [[X:%.*]], -2048
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| ; CHECK-NEXT:    [[B:%.*]] = select i1 [[A]], i16 [[X]], i16 -2048
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| ; CHECK-NEXT:    [[C:%.*]] = icmp slt i16 [[B]], 2047
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| ; CHECK-NEXT:    [[D:%.*]] = select i1 [[C]], i16 [[B]], i16 2047
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| ; CHECK-NEXT:    [[G:%.*]] = sext i16 [[D]] to i32
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| ; CHECK-NEXT:    ret i32 [[G]]
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| ;
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|   %a = icmp sgt i16 %x, -2048
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|   %b = select i1 %a, i16 %x, i16 -2048
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|   %c = icmp slt i16 %b, 2047
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|   %d = select i1 %c, i16 %b, i16 2047
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|   %e = add i16 %d, 1
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|   %f = sext i16 %e to i32
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|   %g = add i32 %f, -1
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|   ret i32 %g
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| }
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| 
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| ; Same as above with min/max order reversed
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| define i32 @min_max_clamp_4(i16 %x) {
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| ; CHECK-LABEL: @min_max_clamp_4(
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| ; CHECK-NEXT:    [[A:%.*]] = icmp slt i16 [[X:%.*]], 2047
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| ; CHECK-NEXT:    [[B:%.*]] = select i1 [[A]], i16 [[X]], i16 2047
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| ; CHECK-NEXT:    [[C:%.*]] = icmp sgt i16 [[B]], -2048
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| ; CHECK-NEXT:    [[D:%.*]] = select i1 [[C]], i16 [[B]], i16 -2048
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| ; CHECK-NEXT:    [[G:%.*]] = sext i16 [[D]] to i32
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| ; CHECK-NEXT:    ret i32 [[G]]
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| ;
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|   %a = icmp slt i16 %x, 2047
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|   %b = select i1 %a, i16 %x, i16 2047
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|   %c = icmp sgt i16 %b, -2048
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|   %d = select i1 %c, i16 %b, i16 -2048
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|   %e = add i16 %d, 1
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|   %f = sext i16 %e to i32
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|   %g = add i32 %f, -1
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|   ret i32 %g
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| }
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