c554c5e159
Last we looked at this and couldn't come up with a reason to change it, but with a pragma for full loop unrolling we bypass every other loop unroll and then fail to fully unroll a loop when the pragma is set. Move the OnlyWhenForced out of the check and into the initialization of the full unroll pass in the new pass manager. This doesn't show up with the old pass manager. Add a new option to opt so that we can turn off loop unrolling manually since this is a difference between clang and opt. Tested with check-clang and check-llvm.
43 lines
1.2 KiB
C
43 lines
1.2 KiB
C
// RUN: %clang -O1 -fexperimental-new-pass-manager -fno-unroll-loops -S -o - %s -emit-llvm | FileCheck %s -check-prefix=CHECK-NEWPM
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// RUN: %clang -O1 -fno-experimental-new-pass-manager -fno-unroll-loops -S -o - %s -emit-llvm | FileCheck %s -check-prefix=CHECK-OLDPM
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extern int a[16];
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int b = 0;
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int foo(void) {
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#pragma unroll
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for (int i = 0; i < 16; ++i)
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a[i] = b += 2;
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return b;
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}
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// Check br i1 to make sure that the loop is fully unrolled
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// CHECK-LABEL-NEWPM: foo
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// CHECK-NOT-NEWPM: br i1
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// CHECK-LABEL-OLDPM: foo
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// CHECK-NOT-OLDPM: br i1
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void Helper() {
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const int *nodes[5];
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int num_active = 5;
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while (num_active)
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#pragma clang loop unroll(full)
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for (int i = 0; i < 5; ++i)
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if (nodes[i])
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--num_active;
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}
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// Check br i1 to make sure the loop is gone, there will still be a label branch for the infinite loop.
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// CHECK-LABEL-NEWPM: Helper
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// CHECK-NEWPM: br label
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// CHECK-NEWPM-NOT: br i1
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// CHECK-NEWPM: br label
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// The old pass manager doesn't remove the while loop so check for 5 load i32*.
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// CHECK-LABEL-OLDPM: Helper
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// CHECK-OLDPM: br label
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// CHECK-OLDPM: load i32*
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// CHECK-OLDPM: load i32*
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// CHECK-OLDPM: load i32*
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// CHECK-OLDPM: load i32*
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// CHECK-OLDPM: load i32*
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// CHECK-OLDPM: ret
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