forked from OSchip/llvm-project
fix a couple typos pointed out by edwin and duncan
llvm-svn: 81219
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@ -2116,7 +2116,7 @@ arbitrarily change its value over its "live range". This is true because the
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"variable" doesn't actually <em>have a live range</em>. Instead, the value is
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"variable" doesn't actually <em>have a live range</em>. Instead, the value is
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logically read from arbitrary registers that happen to be around when needed,
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logically read from arbitrary registers that happen to be around when needed,
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so the value is not neccesarily consistent over time. In fact, %A and %C need
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so the value is not neccesarily consistent over time. In fact, %A and %C need
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to have the same semantics of the core LLVM "replace all uses with" concept
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to have the same semantics or the core LLVM "replace all uses with" concept
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would not hold.</p>
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would not hold.</p>
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<div class="doc_code">
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<div class="doc_code">
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@ -2136,7 +2136,7 @@ can be constant folded to undef because the undef could be an SNaN, and fdiv is
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not (currently) defined on SNaN's. However, in the second example, we can make
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not (currently) defined on SNaN's. However, in the second example, we can make
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a more aggressive assumption: because the undef is allowed to be an arbitrary
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a more aggressive assumption: because the undef is allowed to be an arbitrary
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value, we are allowed to assume that it could be zero. Since a divide by zero
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value, we are allowed to assume that it could be zero. Since a divide by zero
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is has <em>undefined behavior</em>, we are allowed to assume that the operation
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it has <em>undefined behavior</em>, we are allowed to assume that the operation
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does not execute at all. This allows us to delete the divide and all code after
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does not execute at all. This allows us to delete the divide and all code after
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it: since the undefined operation "can't happen", the optimizer can assume that
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it: since the undefined operation "can't happen", the optimizer can assume that
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it occurs in dead code.
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it occurs in dead code.
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