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| author | Jing Yu <jingyu@google.com> | 2010-12-13 12:58:16 -0800 |
|---|---|---|
| committer | Jing Yu <jingyu@google.com> | 2010-12-13 12:58:16 -0800 |
| commit | 2f2d3b42b0ea0c4871518c7b6176bd2b55ae527d (patch) | |
| tree | db6624c9aa28e9c1a2d01121f0757ebda9861c44 /gcc-4.4.3/gcc | |
| parent | b6b198cac722a8dcaa046f0589fe2c2c7caa6a01 (diff) | |
| download | toolchain_gcc-2f2d3b42b0ea0c4871518c7b6176bd2b55ae527d.tar.gz toolchain_gcc-2f2d3b42b0ea0c4871518c7b6176bd2b55ae527d.tar.bz2 toolchain_gcc-2f2d3b42b0ea0c4871518c7b6176bd2b55ae527d.zip | |
Fix a thumb1 code generation bug.
The problem was caused by backporting a patch from upstream without
its necessary dependencies. This patch changes the implementation of
cbranchqi4 so that we keep the optimization without generating
bad code.
Change-Id: Icbaf443ac6e85774cb664036941bf829c5e4c31e
Diffstat (limited to 'gcc-4.4.3/gcc')
| -rw-r--r-- | gcc-4.4.3/gcc/config/arm/arm.md | 43 |
1 files changed, 19 insertions, 24 deletions
diff --git a/gcc-4.4.3/gcc/config/arm/arm.md b/gcc-4.4.3/gcc/config/arm/arm.md index 952cde42e..e9de45efd 100644 --- a/gcc-4.4.3/gcc/config/arm/arm.md +++ b/gcc-4.4.3/gcc/config/arm/arm.md @@ -6411,6 +6411,25 @@ (pc)))] "TARGET_THUMB1" " + /* A pattern to recognize a special situation and optimize for it. + On the thumb, zero-extension from memory is preferrable to sign-extension + due to the available addressing modes. Hence, convert a signed comparison + with zero into an unsigned comparison with 127 if possible. */ + if ((GET_CODE (operands[0]) == LT + || GET_CODE (operands[0]) == GE) + && memory_operand (XEXP (operands[0], 0), QImode) + && const0_operand (XEXP (operands[0], 1), QImode)) + { + rtx xops[4]; + xops[1] = gen_reg_rtx (SImode); + emit_insn (gen_zero_extendqisi2 (xops[1], XEXP (operands[0], 0))); + xops[2] = GEN_INT (127); + xops[0] = gen_rtx_fmt_ee (GET_CODE (operands[0]) == GE ? LEU : GTU, + VOIDmode, xops[1], xops[2]); + xops[3] = operands[3]; + emit_insn (gen_cbranchsi4 (xops[0], xops[1], xops[2], xops[3])); + DONE; + } if (thumb1_cmpneg_operand (operands[2], SImode)) { emit_jump_insn (gen_cbranchsi4_scratch (NULL, operands[1], operands[2], @@ -6421,30 +6440,6 @@ operands[2] = force_reg (SImode, operands[2]); ") -;; A pattern to recognize a special situation and optimize for it. -;; On the thumb, zero-extension from memory is preferrable to sign-extension -;; due to the available addressing modes. Hence, convert a signed comparison -;; with zero into an unsigned comparison with 127 if possible. -(define_expand "cbranchqi4" - [(set (pc) (if_then_else - (match_operator 0 "lt_ge_comparison_operator" - [(match_operand:QI 1 "memory_operand" "") - (match_operand:QI 2 "const0_operand" "")]) - (label_ref (match_operand 3 "" "")) - (pc)))] - "TARGET_THUMB1" -{ - rtx xops[3]; - xops[1] = gen_reg_rtx (SImode); - emit_insn (gen_zero_extendqisi2 (xops[1], operands[1])); - xops[2] = GEN_INT (127); - xops[0] = gen_rtx_fmt_ee (GET_CODE (operands[0]) == GE ? LEU : GTU, - VOIDmode, xops[1], xops[2]); - xops[3] = operands[3]; - emit_insn (gen_cbranchsi4 (xops[0], xops[1], xops[2], xops[3])); - DONE; -}) - (define_insn "*cbranchsi4_insn" [(set (pc) (if_then_else (match_operator 0 "arm_comparison_operator" |