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authorMingming Liu <mingmingl@google.com>2025-09-10 15:25:31 -0700
committerGitHub <noreply@github.com>2025-09-10 15:25:31 -0700
commit1417dafa1db9cb1b2b09438aa9f53ea5ab6e36e2 (patch)
tree57f4b1f313c8cf74eed8819870f39c36ea263c68 /llvm/lib/Target/ARM/README.txt
parent898b813bc8a6d0276bf0f4769f5f2f64b34e632d (diff)
parentb8cefcb601ddaa18482555c4ff363c01a270c2fe (diff)
Merge branch 'main' into users/mingmingl-llvm/samplefdo-profile-formatusers/mingmingl-llvm/samplefdo-profile-format
Diffstat (limited to 'llvm/lib/Target/ARM/README.txt')
-rw-r--r--llvm/lib/Target/ARM/README.txt16
1 files changed, 0 insertions, 16 deletions
diff --git a/llvm/lib/Target/ARM/README.txt b/llvm/lib/Target/ARM/README.txt
index def67cfae727..ff84e07fa084 100644
--- a/llvm/lib/Target/ARM/README.txt
+++ b/llvm/lib/Target/ARM/README.txt
@@ -697,22 +697,6 @@ target-neutral one.
//===---------------------------------------------------------------------===//
-Optimize unnecessary checks for zero with __builtin_clz/ctz. Those builtins
-are specified to be undefined at zero, so portable code must check for zero
-and handle it as a special case. That is unnecessary on ARM where those
-operations are implemented in a way that is well-defined for zero. For
-example:
-
-int f(int x) { return x ? __builtin_clz(x) : sizeof(int)*8; }
-
-should just be implemented with a CLZ instruction. Since there are other
-targets, e.g., PPC, that share this behavior, it would be best to implement
-this in a target-independent way: we should probably fold that (when using
-"undefined at zero" semantics) to set the "defined at zero" bit and have
-the code generator expand out the right code.
-
-//===---------------------------------------------------------------------===//
-
Clean up the test/MC/ARM files to have more robust register choices.
R0 should not be used as a register operand in the assembler tests as it's then