; RUN: opt < %s -loop-reduce -S | FileCheck %s target datalayout = "e-i64:64-v16:16-v32:32-n16:32:64" target triple = "nvptx64-nvidia-cuda" ; This confirms that NVPTXTTI considers a 64-to-32 integer trunc free. If such ; truncs were not considered free, LSR would promote (int)i as a separate ; induction variable in the following example. ; ; for (long i = begin; i != end; i += stride) ; use((int)i); ; ; That would be worthless, because "i" is simulated by two 32-bit registers and ; truncating it to 32-bit is as simple as directly using the register that ; contains the low bits. define void @trunc_is_free(i64 %begin, i64 %stride, i64 %end) { ; CHECK-LABEL: @trunc_is_free( entry: %cmp.4 = icmp eq i64 %begin, %end br i1 %cmp.4, label %for.cond.cleanup, label %for.body.preheader for.body.preheader: ; preds = %entry br label %for.body for.cond.cleanup.loopexit: ; preds = %for.body br label %for.cond.cleanup for.cond.cleanup: ; preds = %for.cond.cleanup.loopexit, %entry ret void for.body: ; preds = %for.body.preheader, %for.body ; CHECK: for.body: %i.05 = phi i64 [ %add, %for.body ], [ %begin, %for.body.preheader ] %conv = trunc i64 %i.05 to i32 ; CHECK: trunc i64 %{{[^ ]+}} to i32 tail call void @_Z3usei(i32 %conv) #2 %add = add nsw i64 %i.05, %stride %cmp = icmp eq i64 %add, %end br i1 %cmp, label %for.cond.cleanup.loopexit, label %for.body } declare void @_Z3usei(i32) !nvvm.annotations = !{!0} !0 = !{void (i64, i64, i64)* @trunc_is_free, !"kernel", i32 1}