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| author | Dmitry Venikov <quolyk@gmail.com> | 2018-01-02 05:58:11 +0000 |
|---|---|---|
| committer | Dmitry Venikov <quolyk@gmail.com> | 2018-01-02 05:58:11 +0000 |
| commit | f45df3f5d598af04970db343f1f0b854236bb7b0 (patch) | |
| tree | 1ca886200bf1fd26d94c39e0d607bd5c060eb225 /test/Transforms | |
| parent | 9579686b841cfc8f6e9b80306cf63b10ee211571 (diff) | |
[InstCombine] Missed optimization in math expression: squashing sqrt functions
Summary: This patch enables folding under -ffast-math flag sqrt(a) * sqrt(b) -> sqrt(a*b)
Reviewers: hfinkel, spatel, davide
Reviewed By: spatel, davide
Subscribers: davide, llvm-commits
Differential Revision: https://reviews.llvm.org/D41322
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321637 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'test/Transforms')
| -rw-r--r-- | test/Transforms/InstCombine/fmul-sqrt.ll | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/test/Transforms/InstCombine/fmul-sqrt.ll b/test/Transforms/InstCombine/fmul-sqrt.ll new file mode 100644 index 00000000000..0031a61059a --- /dev/null +++ b/test/Transforms/InstCombine/fmul-sqrt.ll @@ -0,0 +1,67 @@ +; NOTE: Assertions have been autogenerated by utils/update_test_checks.py +; RUN: opt -S -instcombine < %s | FileCheck %s + +declare double @llvm.sqrt.f64(double) nounwind readnone speculatable +declare void @use(double) + +; sqrt(a) * sqrt(b) no math flags +define double @sqrt_a_sqrt_b(double %a, double %b) { +; CHECK-LABEL: @sqrt_a_sqrt_b( +; CHECK-NEXT: [[TMP1:%.*]] = call double @llvm.sqrt.f64(double [[A:%.*]]) +; CHECK-NEXT: [[TMP2:%.*]] = call double @llvm.sqrt.f64(double [[B:%.*]]) +; CHECK-NEXT: [[MUL:%.*]] = fmul double [[TMP1]], [[TMP2]] +; CHECK-NEXT: ret double [[MUL]] +; + %1 = call double @llvm.sqrt.f64(double %a) + %2 = call double @llvm.sqrt.f64(double %b) + %mul = fmul double %1, %2 + ret double %mul +} + +; sqrt(a) * sqrt(b) fast-math, multiple uses +define double @sqrt_a_sqrt_b_multiple_uses(double %a, double %b) { +; CHECK-LABEL: @sqrt_a_sqrt_b_multiple_uses( +; CHECK-NEXT: [[TMP1:%.*]] = call fast double @llvm.sqrt.f64(double [[A:%.*]]) +; CHECK-NEXT: [[TMP2:%.*]] = call fast double @llvm.sqrt.f64(double [[B:%.*]]) +; CHECK-NEXT: [[MUL:%.*]] = fmul fast double [[TMP1]], [[TMP2]] +; CHECK-NEXT: call void @use(double [[TMP2]]) +; CHECK-NEXT: ret double [[MUL]] +; + %1 = call fast double @llvm.sqrt.f64(double %a) + %2 = call fast double @llvm.sqrt.f64(double %b) + %mul = fmul fast double %1, %2 + call void @use(double %2) + ret double %mul +} + +; sqrt(a) * sqrt(b) => sqrt(a*b) with fast-math +define double @sqrt_a_sqrt_b_fast(double %a, double %b) { +; CHECK-LABEL: @sqrt_a_sqrt_b_fast( +; CHECK-NEXT: [[TMP1:%.*]] = fmul fast double [[A:%.*]], [[B:%.*]] +; CHECK-NEXT: [[TMP2:%.*]] = call fast double @llvm.sqrt.f64(double [[TMP1]]) +; CHECK-NEXT: ret double [[TMP2]] +; + %1 = call fast double @llvm.sqrt.f64(double %a) + %2 = call fast double @llvm.sqrt.f64(double %b) + %mul = fmul fast double %1, %2 + ret double %mul +} + +; sqrt(a) * sqrt(b) * sqrt(c) * sqrt(d) => sqrt(a*b*c+d) with fast-math +define double @sqrt_a_sqrt_b_sqrt_c_sqrt_d_fast(double %a, double %b, double %c, double %d) { +; CHECK-LABEL: @sqrt_a_sqrt_b_sqrt_c_sqrt_d_fast( +; CHECK-NEXT: [[TMP1:%.*]] = fmul fast double [[A:%.*]], [[B:%.*]] +; CHECK-NEXT: [[TMP2:%.*]] = fmul fast double [[TMP1]], [[C:%.*]] +; CHECK-NEXT: [[TMP3:%.*]] = fmul fast double [[TMP2]], [[D:%.*]] +; CHECK-NEXT: [[TMP4:%.*]] = call fast double @llvm.sqrt.f64(double [[TMP3]]) +; CHECK-NEXT: ret double [[TMP4]] +; + %1 = call fast double @llvm.sqrt.f64(double %a) + %2 = call fast double @llvm.sqrt.f64(double %b) + %mul = fmul fast double %1, %2 + %3 = call fast double @llvm.sqrt.f64(double %c) + %mul1 = fmul fast double %mul, %3 + %4 = call fast double @llvm.sqrt.f64(double %d) + %mul2 = fmul fast double %mul1, %4 + ret double %mul2 +} |